Document and Entity Information - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Feb. 22, 2019 |
Jun. 29, 2018 |
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| Document Information [Line Items] | |||
| Document Type | 10-K | ||
| Amendment Flag | false | ||
| Document Period End Date | Dec. 31, 2018 | ||
| Document Fiscal Year Focus | 2018 | ||
| Document Fiscal Period Focus | FY | ||
| Trading Symbol | UAL | ||
| Entity Registrant Name | United Continental Holdings, Inc. | ||
| Entity Central Index Key | 0000100517 | ||
| Current Fiscal Year End Date | --12-31 | ||
| Entity Well-known Seasoned Issuer | Yes | ||
| Entity Current Reporting Status | Yes | ||
| Entity Voluntary Filers | No | ||
| Entity Filer Category | Large Accelerated Filer | ||
| Entity Common Stock, Shares Outstanding | 266,727,577 | ||
| Entity Public Float | $ 17,844,650,113 | ||
| United Airlines, Inc. | |||
| Document Information [Line Items] | |||
| Entity Registrant Name | United Airlines, Inc. | ||
| Entity Central Index Key | 0000319687 | ||
| Current Fiscal Year End Date | --12-31 | ||
| Entity Filer Category | Non-accelerated Filer | ||
| Entity Common Stock, Shares Outstanding | 1,000 |
| X | ||||||||||
- Definition If the value is true, then the document is an amendment to previously-filed/accepted document. No definition available.
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- Definition End date of current fiscal year in the format --MM-DD. No definition available.
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- Definition This is focus fiscal period of the document report. For a first quarter 2006 quarterly report, which may also provide financial information from prior periods, the first fiscal quarter should be given as the fiscal period focus. Values: FY, Q1, Q2, Q3, Q4, H1, H2, M9, T1, T2, T3, M8, CY. No definition available.
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- Definition This is focus fiscal year of the document report in CCYY format. For a 2006 annual report, which may also provide financial information from prior periods, fiscal 2006 should be given as the fiscal year focus. Example: 2006. No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD. No definition available.
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- Definition The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word "Other". No definition available.
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- Definition A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Indicate number of shares or other units outstanding of each of registrant's classes of capital or common stock or other ownership interests, if and as stated on cover of related periodic report. Where multiple classes or units exist define each class/interest by adding class of stock items such as Common Class A [Member], Common Class B [Member] or Partnership Interest [Member] onto the Instrument [Domain] of the Entity Listings, Instrument. No definition available.
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- Definition Indicate "Yes" or "No" whether registrants (1) have filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that registrants were required to file such reports), and (2) have been subject to such filing requirements for the past 90 days. This information should be based on the registrant's current or most recent filing containing the related disclosure. No definition available.
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- Definition Indicate whether the registrant is one of the following: (1) Large Accelerated Filer, (2) Accelerated Filer, (3) Non-accelerated Filer, (4) Smaller Reporting Company (Non-accelerated) or (5) Smaller Reporting Accelerated Filer. Definitions of these categories are stated in Rule 12b-2 of the Exchange Act. This information should be based on the registrant's current or most recent filing containing the related disclosure. No definition available.
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- Definition State aggregate market value of voting and non-voting common equity held by non-affiliates computed by reference to price at which the common equity was last sold, or average bid and asked price of such common equity, as of the last business day of registrant's most recently completed second fiscal quarter. The public float should be reported on the cover page of the registrants form 10K. No definition available.
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- Definition The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Indicate "Yes" or "No" if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. No definition available.
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- Definition Indicate "Yes" or "No" if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Is used on Form Type: 10-K, 10-Q, 8-K, 20-F, 6-K, 10-K/A, 10-Q/A, 20-F/A, 6-K/A, N-CSR, N-Q, N-1A. No definition available.
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- Definition Trading symbol of an instrument as listed on an exchange. No definition available.
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- Details
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Statements of Consolidated Operations - USD ($) $ in Millions |
12 Months Ended | ||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Operating revenue: | |||||||||||||||||||||
| Revenue | $ 41,303 | $ 37,784 | [1] | $ 36,558 | [1] | ||||||||||||||||
| Operating expense: | |||||||||||||||||||||
| Salaries and related costs | 11,458 | 10,941 | [1] | 10,176 | [1] | ||||||||||||||||
| Aircraft fuel | 9,307 | 6,913 | [1] | 5,813 | [1] | ||||||||||||||||
| Regional capacity purchase | 2,601 | 2,232 | [1] | 2,197 | [1] | ||||||||||||||||
| Landing fees and other rent | 2,359 | 2,240 | [1] | 2,165 | [1] | ||||||||||||||||
| Depreciation and amortization | 2,240 | 2,149 | [1],[2] | 1,977 | [1],[2] | ||||||||||||||||
| Aircraft maintenance materials and outside repairs | 1,767 | 1,856 | [1] | 1,749 | [1] | ||||||||||||||||
| Distribution expenses | 1,558 | 1,435 | [1] | 1,395 | [1] | ||||||||||||||||
| Aircraft rent | 433 | 621 | [1] | 680 | [1] | ||||||||||||||||
| Special charges | 487 | 176 | [1] | 745 | [1] | ||||||||||||||||
| Other operating expenses | 5,801 | 5,550 | [1] | 5,317 | [1] | ||||||||||||||||
| Total operating expense | 38,011 | 34,113 | [1] | 32,214 | [1] | ||||||||||||||||
| Operating income | 3,292 | 3,671 | [1] | 4,344 | [1] | ||||||||||||||||
| Nonoperating income (expense): | |||||||||||||||||||||
| Interest expense | (729) | (671) | [1] | (674) | [1] | ||||||||||||||||
| Interest capitalized | 70 | 84 | [1] | 72 | [1] | ||||||||||||||||
| Interest income | 101 | 57 | [1] | 42 | [1] | ||||||||||||||||
| Miscellaneous, net | (76) | (101) | [1] | (11) | [1] | ||||||||||||||||
| Total nonoperating expense, net | (634) | (631) | [1] | (571) | [1] | ||||||||||||||||
| Income before income taxes | 2,658 | 3,040 | [1] | 3,773 | [1] | ||||||||||||||||
| Income tax expense | 529 | 896 | [1] | 1,539 | [1] | ||||||||||||||||
| Net income | $ 2,129 | $ 2,144 | [1],[2],[3],[4] | $ 2,234 | [1],[2],[3],[4] | ||||||||||||||||
| Earnings per share, basic (in dollars per share) | $ 7.73 | $ 7.08 | [1] | $ 6.77 | [1] | ||||||||||||||||
| Earnings per share, diluted (in dollars per share) | $ 7.70 | $ 7.06 | [1] | $ 6.76 | [1] | ||||||||||||||||
| United Airlines, Inc. | |||||||||||||||||||||
| Operating revenue: | |||||||||||||||||||||
| Revenue | $ 41,303 | $ 37,784 | [5] | $ 36,558 | [5] | ||||||||||||||||
| Operating expense: | |||||||||||||||||||||
| Salaries and related costs | 11,458 | 10,941 | [5] | 10,176 | [5] | ||||||||||||||||
| Aircraft fuel | 9,307 | 6,913 | [5] | 5,813 | [5] | ||||||||||||||||
| Regional capacity purchase | 2,601 | 2,232 | [5] | 2,197 | [5] | ||||||||||||||||
| Landing fees and other rent | 2,359 | 2,240 | [5] | 2,165 | [5] | ||||||||||||||||
| Depreciation and amortization | 2,240 | 2,149 | [5],[6] | 1,977 | [5],[6] | ||||||||||||||||
| Aircraft maintenance materials and outside repairs | 1,767 | 1,856 | [5] | 1,749 | [5] | ||||||||||||||||
| Distribution expenses | 1,558 | 1,435 | [5] | 1,395 | [5] | ||||||||||||||||
| Aircraft rent | 433 | 621 | [5] | 680 | [5] | ||||||||||||||||
| Special charges | 487 | 176 | [5] | 745 | [5] | ||||||||||||||||
| Other operating expenses | 5,799 | 5,548 | [5] | 5,315 | [5] | ||||||||||||||||
| Total operating expense | 38,009 | 34,111 | [5] | 32,212 | [5] | ||||||||||||||||
| Operating income | 3,294 | 3,673 | [5] | 4,346 | [5] | ||||||||||||||||
| Nonoperating income (expense): | |||||||||||||||||||||
| Interest expense | (729) | (671) | [5] | (674) | [5] | ||||||||||||||||
| Interest capitalized | 70 | 84 | [5] | 72 | [5] | ||||||||||||||||
| Interest income | 101 | 57 | [5] | 42 | [5] | ||||||||||||||||
| Miscellaneous, net | (76) | (101) | [5] | (11) | [5] | ||||||||||||||||
| Total nonoperating expense, net | (634) | (631) | [5] | (571) | [5] | ||||||||||||||||
| Income before income taxes | 2,660 | 3,042 | [5] | 3,775 | [5] | ||||||||||||||||
| Income tax expense | 529 | 879 | [5] | 1,541 | [5] | ||||||||||||||||
| Net income | 2,131 | 2,163 | [6],[7],[8] | 2,234 | [6],[7],[8] | ||||||||||||||||
| Passenger revenue | |||||||||||||||||||||
| Operating revenue: | |||||||||||||||||||||
| Revenue | 37,706 | 34,460 | [1] | 33,429 | [1] | ||||||||||||||||
| Passenger revenue | United Airlines, Inc. | |||||||||||||||||||||
| Operating revenue: | |||||||||||||||||||||
| Revenue | 37,706 | 34,460 | [5] | 33,429 | [5] | ||||||||||||||||
| Cargo | |||||||||||||||||||||
| Operating revenue: | |||||||||||||||||||||
| Revenue | 1,237 | 1,114 | [1] | 934 | [1] | ||||||||||||||||
| Cargo | United Airlines, Inc. | |||||||||||||||||||||
| Operating revenue: | |||||||||||||||||||||
| Revenue | 1,237 | 1,114 | [5] | 934 | [5] | ||||||||||||||||
| Other operating revenue | |||||||||||||||||||||
| Operating revenue: | |||||||||||||||||||||
| Revenue | 2,360 | 2,210 | [1] | 2,195 | [1] | ||||||||||||||||
| Other operating revenue | United Airlines, Inc. | |||||||||||||||||||||
| Operating revenue: | |||||||||||||||||||||
| Revenue | $ 2,360 | $ 2,210 | [5] | $ 2,195 | [5] | ||||||||||||||||
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- Definition Maintenance costs incurred and directly related to services rendered by an entity during the reporting period. Includes the cost of inspections and repairs, materials and routine maintenance costs for all aircraft and engines. No definition available.
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- Definition Expenses incurred related to the lease of aircraft from outside third parties that are used in the entity's business operations. No definition available.
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- Definition Costs incurred related to air services provided by third-party transportation companies, including regional affiliates. No definition available.
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- Definition Total costs of sales and operating expenses for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Fuel costs incurred that are directly related to goods produced and sold and services rendered during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of interest costs capitalized disclosed as an adjusting item to interest costs incurred. No definition available.
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- Definition Amount of the cost of borrowed funds accounted for as interest expense. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate amount of expenditures for salaries, wages, profit sharing and incentive compensation, and other employee benefits, including equity-based compensation, and pension and other postretirement benefit expense. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Direct costs incurred at airports in which the entity conducts flight operations. The costs primarily consist of fees paid to the airport authority for takeoff and landing, gate space and facilities, allocations of common space such as security and other terminal costs and fuel storage facilities. No definition available.
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| X | ||||||||||
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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| X | ||||||||||
- Definition The net result for the period of deducting operating expenses from operating revenues. No definition available.
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- Definition The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of income (expense) related to nonoperating activities, classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of restructuring charges, remediation cost, and asset impairment loss. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Expenses recognized in the period that are directly related to the selling and distribution of products or services. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Details
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- Details
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- Details
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Statements of Consolidated Comprehensive Income (Loss) - USD ($) $ in Millions |
12 Months Ended | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Net income | $ 2,129 | $ 2,144 | [1],[2],[3],[4] | $ 2,234 | [1],[2],[3],[4] | ||||||||||||||
| Other comprehensive income (loss), net change related to: | |||||||||||||||||||
| Employee benefit plans, net of taxes | 342 | (195) | (313) | ||||||||||||||||
| Fuel derivative financial instruments, net of taxes | 0 | 1 | 316 | ||||||||||||||||
| Investments and other, net of taxes | (4) | (6) | (1) | ||||||||||||||||
| Total other comprehensive income (loss), net | 338 | (200) | 2 | ||||||||||||||||
| Total comprehensive income, net | 2,467 | 1,944 | 2,236 | ||||||||||||||||
| United Airlines, Inc. | |||||||||||||||||||
| Net income | 2,131 | 2,163 | [5],[6],[7] | 2,234 | [5],[6],[7] | ||||||||||||||
| Other comprehensive income (loss), net change related to: | |||||||||||||||||||
| Employee benefit plans, net of taxes | 342 | (195) | [5] | (313) | [5] | ||||||||||||||
| Fuel derivative financial instruments, net of taxes | 0 | 1 | [5] | 316 | [5] | ||||||||||||||
| Investments and other, net of taxes | (4) | (6) | [5] | (1) | [5] | ||||||||||||||
| Total other comprehensive income (loss), net | 338 | (200) | [5] | 2 | [5] | ||||||||||||||
| Total comprehensive income, net | $ 2,469 | $ 1,963 | [5] | $ 2,236 | [5] | ||||||||||||||
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- Definition Other Comprehensive Income, Investments and Other, Net of Tax No definition available.
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| X | ||||||||||
- Definition Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount after tax and reclassification adjustments of other comprehensive income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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| X | ||||||||||
- Definition Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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| X | ||||||||||
- Definition Amount of liabilities incurred to vendors for goods and services received, and accrued liabilities classified as other, payable within one year or the normal operating cycle, if longer. No definition available.
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| X | ||||||||||
- Definition Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Value received from shareholders in common stock-related transactions that are in excess of par value or stated value and amounts received from other stock-related transactions. Includes only common stock transactions (excludes preferred stock transactions). May be called contributed capital, capital in excess of par, capital surplus, or paid-in capital. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The value of air transportation services sold but as yet unused by the passenger, including sales for air transportation to be provided by the reporting air carrier and air transportation to be provided by another air carrier for whom sales were made. Used to reflect the current portion of the liability (within one year or within the normal operating cycle if longer). No definition available.
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| X | ||||||||||
- Definition Net carrying amount, as of the balance sheet date, of expendable merchandise, goods, commodities, or supplies to be used primarily in air transport of passengers and freight. No definition available.
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| X | ||||||||||
- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold, or consumed within one year (or the normal operating cycle, if longer). Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Amount of capital lease obligation due within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount before accumulated depreciation of leased physical assets used in the normal conduct of business to produce goods and services. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The total gross amount less the charge for the use of the long-lived depreciable assets subject to a lease meeting the criteria for capitalization. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Gross amount of long-lived, depreciable flight assets used in the entity's principle business operations, subject to a lease and meeting the criteria for capitalization. No definition available.
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| X | ||||||||||
- Definition Amount before depreciation of leased long-lived, physical assets used to produce goods and services and not intended for resale meeting the criteria for capitalization, classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Represents the caption on the face of the balance sheet to indicate that the entity has entered into (1) purchase or supply arrangements that will require expending a portion of its resources to meet the terms thereof, and (2) is exposed to potential losses or, less frequently, gains, arising from (a) possible claims against a company's resources due to future performance under contract terms, and (b) possible losses or likely gains from uncertainties that will ultimately be resolved when one or more future events that are deemed likely to occur do occur or fail to occur. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension plan, classified as noncurrent. Excludes other postretirement benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Carrying amount, at the balance sheet date, of deposits made to the manufacturer for new flight equipment still under construction. May include capitalized interest. No definition available.
|
| X | ||||||||||
- Definition Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The gross amount of long-lived, depreciable flight assets used in the entity's principle business operations, including owned aircraft and on capital lease, as well as capitalized improvements. No definition available.
|
| X | ||||||||||
- Definition Value of revenue deferred or cost to provide future products or services, primarily air transportation, associated with programs used by airlines to encourage passenger loyalty by providing rewards geared to the frequency of travel on the sponsoring airline, typically in the form of frequent flyer miles, points, or segments that can be accumulated and converted into free or discounted travel or other redemption options. Used to reflect the current portion of the liability (within one year or within the normal operating cycle if longer). No definition available.
|
| X | ||||||||||
- Definition Value of revenue deferred or cost to provide future products or services, primarily air transportation, associated with programs used by airlines to encourage passenger loyalty by providing rewards geared to the frequency of travel on the sponsoring airline, typically in the form of frequent flyer miles, points, or segments that can be accumulated and converted into free or discounted travel or other redemption options. Used to reflect the noncurrent portion of the liability. No definition available.
|
| X | ||||||||||
- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of investments, and noncurrent assets classified as other. No definition available.
|
| X | ||||||||||
- Definition Amount of liabilities and equity items, including the portion of equity attributable to noncontrolling interests, if any. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Total obligations incurred as part of normal operations that are expected to be paid during the following twelve months or within one business cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date more than one year from the balance sheet date, net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of noncurrent assets classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of liability, recognized in statement of financial position, for defined benefit other postretirement plan, classified as noncurrent. Excludes pension plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are expected to be paid after one year (or the normal operating cycle, if longer), from the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Aggregate par or stated value of issued nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable preferred shares, par value and other disclosure concepts are in another section within stockholders' equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount before accumulated depreciation, depletion and amortization of other physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The cumulative amount of depreciation (related to long-lived, depreciable flight assets owned by the entity and used in the entity's principle business operations and capitalized assets classified as property, plant and equipment that are owned by the entity) that has been recognized in the income statement. No definition available.
|
| X | ||||||||||
- Definition Gross amount of long-lived, depreciable flight assets owned by the entity and used in the entity's principle business operations (owned aircraft and capitalized improvements) and capitalized assets classified as property, plant and equipment that are owned by the entity. Excludes assets subject to a capital lease. No definition available.
|
| X | ||||||||||
- Definition The net amount of long-lived, depreciable flight assets owned by the entity and used in the entity's principle business operations (owned aircraft and capitalized improvements) and capitalized assets classified as property, plant and equipment that are owned by the entity. Excludes assets subject to a capital lease. No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amounts due from owners or affiliates of the reporting entity related to issuance of the entity's capital stock before cash payment is received (does not include amounts due from officers or directors). This element would also include the receivable for proceeds from the issuance of shares under employee stock option exercises which proceeds have not been received as of the reporting date due to the timing of the transaction date versus the settlement date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cumulative amount of the reporting entity's undistributed earnings or deficit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Details
|
Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions |
Dec. 31, 2018 |
Dec. 31, 2017 |
|||||
|---|---|---|---|---|---|---|---|
| Receivables, allowance for doubtful accounts | $ 8 | $ 7 | [1] | ||||
| Aircraft fuel, spare parts and supplies, obsolescence allowance | 412 | 354 | [1] | ||||
| Intangibles, accumulated amortization | $ 1,380 | $ 1,313 | [1] | ||||
| Common stock, par value (in dollars per share) | $ 0.01 | $ 0.01 | [1] | ||||
| Common shares, authorized (in shares) | 1,000,000,000 | 1,000,000,000 | [1] | ||||
| Common shares, outstanding (in shares) | 269,914,769 | 286,973,195 | [1] | ||||
| United Airlines, Inc. | |||||||
| Receivables, allowance for doubtful accounts | $ 8 | $ 7 | [2] | ||||
| Aircraft fuel, spare parts and supplies, obsolescence allowance | 412 | 354 | [2] | ||||
| Intangibles, accumulated amortization | $ 1,380 | $ 1,313 | [2] | ||||
| Common stock, par value (in dollars per share) | $ 0.01 | $ 0.01 | [2] | ||||
| Common shares, authorized (in shares) | 1,000 | 1,000 | [2] | ||||
| Common shares, issued (in shares) | 1,000 | 1,000 | [2] | ||||
| Common shares, outstanding (in shares) | 1,000 | 1,000 | [2] | ||||
| |||||||
| X | ||||||||||
- Definition The amount of the valuation account as of the balance sheet date which reduces the carrying amount of airline related inventory (including expendable merchandise, goods, commodities, or supplies to be used primarily in air transport of passengers or freight) to net realizable value; takes into consideration such factors as market value, excessive quantities based on expected sales, technological obsolescence, and shrinkage. No definition available.
|
| X | ||||||||||
- Definition A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Face amount or stated value per share of common stock. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The maximum number of common shares permitted to be issued by an entity's charter and bylaws. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Details
|
Statements of Consolidated Cash Flows - USD ($) $ in Millions |
12 Months Ended | |||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
||||||||||||||||||||
| Operating Activities: | ||||||||||||||||||||||
| Net income | $ 2,129 | $ 2,144 | [1],[2],[3],[4] | $ 2,234 | [1],[2],[3],[4] | |||||||||||||||||
| Adjustments to reconcile net income to net cash provided by operating activities - | ||||||||||||||||||||||
| Deferred income taxes | 515 | 973 | [3] | 1,631 | [3] | |||||||||||||||||
| Depreciation and amortization | 2,240 | 2,149 | [1],[3] | 1,977 | [1],[3] | |||||||||||||||||
| Special charges, non-cash portion | 416 | 35 | [3] | 391 | [3] | |||||||||||||||||
| Other operating activities | 170 | 141 | [3] | 109 | [3] | |||||||||||||||||
| Changes in operating assets and liabilities - | ||||||||||||||||||||||
| Increase in receivables | (29) | (183) | [3] | (16) | [3] | |||||||||||||||||
| (Increase) decrease in other assets | 29 | (533) | [3] | (296) | [3] | |||||||||||||||||
| Increase (decrease) in advance ticket sales | 441 | 145 | [3] | (28) | [3] | |||||||||||||||||
| Increase (decrease) in frequent flyer deferred revenue | 222 | (107) | [3] | (55) | [3] | |||||||||||||||||
| Increase in accounts payable | 130 | 66 | [3] | 239 | [3] | |||||||||||||||||
| Decrease in advanced purchase of miles | 0 | (942) | [3] | (206) | [3] | |||||||||||||||||
| Decrease in other liabilities | (82) | (475) | [3] | (438) | [3] | |||||||||||||||||
| Net cash provided by operating activities | 6,181 | 3,413 | [3] | 5,542 | [3] | |||||||||||||||||
| Investing Activities: | ||||||||||||||||||||||
| Capital expenditures | (4,177) | (3,998) | [3] | (3,223) | [3] | |||||||||||||||||
| Purchases of short-term and other investments | (2,552) | (3,241) | [3] | (2,768) | [3] | |||||||||||||||||
| Proceeds from sale of short-term and other investments | 2,616 | 3,177 | [3] | 2,712 | [3] | |||||||||||||||||
| Loans made to others | (466) | (30) | [3] | (56) | [3] | |||||||||||||||||
| Investment in affiliates | (139) | (2) | [3] | (14) | [3] | |||||||||||||||||
| Other, net | 155 | 164 | [3] | 111 | [3] | |||||||||||||||||
| Net cash used in investing activities | (4,563) | (3,930) | [3] | (3,238) | [3] | |||||||||||||||||
| Financing Activities: | ||||||||||||||||||||||
| Proceeds from issuance of long-term debt and airport construction financing | 1,740 | 2,765 | [3] | 808 | [3] | |||||||||||||||||
| Payments of long-term debt | (1,727) | (901) | [3] | (1,215) | [3] | |||||||||||||||||
| Repurchases of common stock | (1,235) | (1,844) | [3] | (2,614) | [3] | |||||||||||||||||
| Principal payments under capital leases | (134) | (124) | [3] | (136) | [3] | |||||||||||||||||
| Capitalized financing costs | (37) | (80) | [3] | (64) | [3] | |||||||||||||||||
| Other, net | (17) | (11) | [3] | 8 | [3] | |||||||||||||||||
| Net cash used in financing activities | (1,410) | (195) | [3] | (3,213) | [3] | |||||||||||||||||
| Net increase (decrease) in cash, cash equivalents and restricted cash | 208 | (712) | [3] | (909) | [3] | |||||||||||||||||
| Cash, cash equivalents and restricted cash at beginning of year | [3] | 1,591 | 2,303 | 3,212 | ||||||||||||||||||
| Cash, cash equivalents and restricted cash at end of year | 1,799 | 1,591 | [3] | 2,303 | [3] | |||||||||||||||||
| Investing and Financing Activities Not Affecting Cash: | ||||||||||||||||||||||
| Property and equipment acquired through the issuance of debt and capital leases | 174 | 935 | [3] | 386 | [3] | |||||||||||||||||
| Debt associated with termination of a maintenance service agreement | 163 | 0 | [3] | 0 | [3] | |||||||||||||||||
| Investment in Republic Airways Holdings, Inc. received from bankruptcy claims | 0 | 92 | [3] | 0 | [3] | |||||||||||||||||
| Airport construction financing | 12 | 42 | [3] | 91 | [3] | |||||||||||||||||
| Operating lease conversions to capital lease | 52 | 0 | [3] | 12 | [3] | |||||||||||||||||
| Cash Paid During the Period for: | ||||||||||||||||||||||
| Interest | 651 | 571 | [3] | 584 | [3] | |||||||||||||||||
| Income taxes | 19 | 20 | [3] | 14 | [3] | |||||||||||||||||
| United Airlines, Inc. | ||||||||||||||||||||||
| Operating Activities: | ||||||||||||||||||||||
| Net income | 2,131 | 2,163 | [5],[6],[7] | 2,234 | [5],[6],[7] | |||||||||||||||||
| Adjustments to reconcile net income to net cash provided by operating activities - | ||||||||||||||||||||||
| Deferred income taxes | 515 | 956 | [6] | 1,633 | [6] | |||||||||||||||||
| Depreciation and amortization | 2,240 | 2,149 | [6],[8] | 1,977 | [6],[8] | |||||||||||||||||
| Special charges, non-cash portion | 416 | 35 | [6] | 391 | [6] | |||||||||||||||||
| Other operating activities | 170 | 140 | [6] | 109 | [6] | |||||||||||||||||
| Changes in operating assets and liabilities - | ||||||||||||||||||||||
| Increase in receivables | (29) | (183) | [6] | (16) | [6] | |||||||||||||||||
| Increase in intercompany receivables | (20) | (15) | [6] | (57) | [6] | |||||||||||||||||
| (Increase) decrease in other assets | 29 | (533) | [6] | (250) | [6] | |||||||||||||||||
| Increase (decrease) in advance ticket sales | 441 | 145 | [6] | (28) | [6] | |||||||||||||||||
| Increase (decrease) in frequent flyer deferred revenue | 222 | (107) | [6] | (55) | [6] | |||||||||||||||||
| Increase in accounts payable | 130 | 66 | [6] | 239 | [6] | |||||||||||||||||
| Decrease in advanced purchase of miles | 0 | (942) | [6] | (206) | [6] | |||||||||||||||||
| Decrease in other liabilities | (82) | (475) | [6] | (436) | [6] | |||||||||||||||||
| Net cash provided by operating activities | 6,163 | 3,399 | [6] | 5,535 | [6] | |||||||||||||||||
| Investing Activities: | ||||||||||||||||||||||
| Capital expenditures | (4,177) | (3,998) | [6] | (3,223) | [6] | |||||||||||||||||
| Proceeds from sale of short-term and other investments | (2,552) | (3,241) | [6] | (2,768) | [6] | |||||||||||||||||
| Proceeds from sale of short-term and other investments | 2,616 | 3,177 | [6] | 2,712 | [6] | |||||||||||||||||
| Loans made to others | (466) | (30) | [6] | (56) | [6] | |||||||||||||||||
| Investment in affiliates | (139) | (2) | [6] | (14) | [6] | |||||||||||||||||
| Other, net | 155 | 164 | [6] | 111 | [6] | |||||||||||||||||
| Net cash used in investing activities | (4,563) | (3,930) | [6] | (3,238) | [6] | |||||||||||||||||
| Financing Activities: | ||||||||||||||||||||||
| Proceeds from issuance of long-term debt and airport construction financing | 1,740 | 2,765 | [6] | 808 | [6] | |||||||||||||||||
| Payments of long-term debt | (1,727) | (901) | [6] | (1,215) | [6] | |||||||||||||||||
| Dividend to UAL | (1,235) | (1,844) | [6] | (2,614) | [6] | |||||||||||||||||
| Principal payments under capital leases | (134) | (124) | [6] | (136) | [6] | |||||||||||||||||
| Capitalized financing costs | (37) | (80) | [6] | (64) | [6] | |||||||||||||||||
| Other, net | 1 | 3 | [6] | 15 | [6] | |||||||||||||||||
| Net cash used in financing activities | (1,392) | (181) | [6] | (3,206) | [6] | |||||||||||||||||
| Net increase (decrease) in cash, cash equivalents and restricted cash | 208 | (712) | [6] | (909) | [6] | |||||||||||||||||
| Cash, cash equivalents and restricted cash at beginning of year | [6] | 1,585 | 2,297 | 3,206 | ||||||||||||||||||
| Cash, cash equivalents and restricted cash at end of year | 1,793 | 1,585 | [6] | 2,297 | [6] | |||||||||||||||||
| Investing and Financing Activities Not Affecting Cash: | ||||||||||||||||||||||
| Property and equipment acquired through the issuance of debt and capital leases | 174 | 935 | [6] | 386 | [6] | |||||||||||||||||
| Debt associated with termination of a maintenance service agreement | 163 | 0 | [6] | 0 | [6] | |||||||||||||||||
| Investment in Republic Airways Holdings, Inc. received from bankruptcy claims | 0 | 92 | [6] | 0 | [6] | |||||||||||||||||
| Airport construction financing | 12 | 42 | [6] | 91 | [6] | |||||||||||||||||
| Operating lease conversions to capital lease | 52 | 0 | [6] | 12 | [6] | |||||||||||||||||
| Cash Paid During the Period for: | ||||||||||||||||||||||
| Interest | 651 | 571 | [6] | 584 | [6] | |||||||||||||||||
| Income taxes | $ 19 | $ 20 | [6] | $ 14 | [6] | |||||||||||||||||
| ||||||||||||||||||||||
| X | ||||||||||
- Definition Capital Lease Conversion From Operating Lease Recorded Property Plant And Equipment No definition available.
|
| X | ||||||||||
- Definition Cash Paid Refunded During Period For [Abstract] No definition available.
|
| X | ||||||||||
- Definition Equity interest received in consideration for bankruptcy claims. No definition available.
|
| X | ||||||||||
- Definition Increase (decrease) in advanced purchase of miles. No definition available.
|
| X | ||||||||||
- Definition Increase (decrease) in frequent flyer deferred revenue. No definition available.
|
| X | ||||||||||
- Definition Non cash obligation for property plant and equipment. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. No definition available.
|
| X | ||||||||||
- Definition Payments of dividends to parent company. No definition available.
|
| X | ||||||||||
- Definition Termination Of Maintenance Service Agreement, Noncash No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of increase (decrease) in cash, cash equivalents, and cash and cash equivalents restricted to withdrawal or usage; including effect from exchange rate change. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The increase (decrease) during the reporting period in receivables to be collected from an entity that is controlling, under the control of, or within the same control group as the reporting entity by means of direct or indirect ownership. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The increase (decrease) during the reporting period in the amount of unearned revenue related to tickets sold but not yet recognized as revenue. No definition available.
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| X | ||||||||||
- Definition Amount of increase (decrease) in operating assets classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Amount of increase (decrease) in operating liabilities classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The increase (decrease) during the reporting period in the total amount due within one year (or one operating cycle) from all parties, associated with underlying transactions that are classified as operating activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of cash paid, after deduction of cash paid for capitalized interest, for interest. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The amount of fixed assets that an Entity acquires in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Other cash or noncash adjustments to reconcile net income to cash provided by (used in) operating activities that are not separately disclosed in the statement of cash flows (for example, cash received or cash paid during the current period for miscellaneous operating activities, net change during the reporting period in other assets or other liabilities). No definition available.
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| X | ||||||||||
- Definition The net cash paid (received) associated with the acquisition or disposal of all investments, including securities and other assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of cash (inflow) outflow from investing activities classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash outflow to reacquire common stock during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash outflow associated with the acquisition of or advances to an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, and joint venture or equity method investment) or the acquisition of an additional interest in a subsidiary (controlled entity). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash outflow associated with the purchase of all investments (debt, security, other) during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash outflow for the purchase of loan receivable arising from the financing of goods and services. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash outflow for securities or other assets acquired, which qualify for treatment as an investing activity and are to be liquidated, if necessary, within the current operating cycle. Includes cash flows from securities classified as trading securities that were acquired for reasons other than sale in the short-term. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of cash inflow (outflow) from financing activities classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash outflow for the obligation for a lease meeting the criteria for capitalization (with maturities exceeding one year or beyond the operating cycle of the entity, if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Details
|
Statements of Consolidated Stockholder's Equity - USD ($) $ in Millions |
Total |
United Airlines, Inc. |
Common Stock |
Additional Capital Invested |
Additional Capital Invested
United Airlines, Inc.
|
Treasury Stock |
Retained Earnings (Accumulated Deficit) |
Retained Earnings (Accumulated Deficit)
United Airlines, Inc.
|
Accumulated Other Comprehensive Income (Loss) |
Accumulated Other Comprehensive Income (Loss)
United Airlines, Inc.
|
Receivable from Related Parties, Net
United Airlines, Inc.
|
||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Balance (in shares) at Dec. 31, 2015 | 364,600,000 | ||||||||||||||||||||||||||||||||||
| Balance at Dec. 31, 2015 | $ 8,966 | $ 8,963 | $ 4 | $ 7,946 | $ 6,138 | $ (1,610) | $ 3,457 | $ 3,673 | $ (831) | $ (831) | $ (17) | ||||||||||||||||||||||||
| Net income | 2,234 | [1],[2],[3],[4] | 2,234 | [5],[6],[7] | 2,234 | [4] | 2,234 | [7],[8] | |||||||||||||||||||||||||||
| Other comprehensive income (loss) | 2 | 2 | [5] | 2 | 2 | ||||||||||||||||||||||||||||||
| Stock-settled share-based compensation | 32 | 32 | 32 | 32 | |||||||||||||||||||||||||||||||
| Dividend to UAL | (2,603) | (2,603) | |||||||||||||||||||||||||||||||||
| Proceeds from exercise of stock options / net treasury stock issued for share-based awards (in shares) | 300,000 | ||||||||||||||||||||||||||||||||||
| Proceeds from exercise of stock options | 6 | 6 | |||||||||||||||||||||||||||||||||
| Repurchases of common stock (in shares) | (50,300,000) | ||||||||||||||||||||||||||||||||||
| Repurchases of common stock | (2,607) | (2,607) | |||||||||||||||||||||||||||||||||
| Treasury stock retired | $ (1) | (1,415) | 3,709 | (2,293) | |||||||||||||||||||||||||||||||
| UAL contribution related to stock plans | 6 | 6 | |||||||||||||||||||||||||||||||||
| Other | (59) | (114) | (3) | (56) | (56) | (58) | |||||||||||||||||||||||||||||
| Balance (in shares) at Dec. 31, 2016 | 314,600,000 | ||||||||||||||||||||||||||||||||||
| Balance at Dec. 31, 2016 | 8,574 | 8,520 | $ 3 | 6,569 | 3,573 | (511) | 3,342 | 5,851 | (829) | (829) | (75) | ||||||||||||||||||||||||
| Net income | 2,144 | [1],[2],[3],[4] | 2,163 | [5],[6],[7] | 2,144 | [4] | 2,163 | [7],[8] | |||||||||||||||||||||||||||
| Other comprehensive income (loss) | (200) | (200) | [5] | (200) | (200) | ||||||||||||||||||||||||||||||
| Stock-settled share-based compensation | 56 | 56 | 56 | 56 | |||||||||||||||||||||||||||||||
| Dividend to UAL | (1,844) | (1,844) | |||||||||||||||||||||||||||||||||
| Proceeds from exercise of stock options / net treasury stock issued for share-based awards (in shares) | 200,000 | ||||||||||||||||||||||||||||||||||
| Proceeds from exercise of stock options | 2 | 2 | |||||||||||||||||||||||||||||||||
| Repurchases of common stock (in shares) | (27,800,000) | ||||||||||||||||||||||||||||||||||
| Repurchases of common stock | (1,844) | (1,844) | |||||||||||||||||||||||||||||||||
| Treasury stock retired | (508) | 1,576 | (1,068) | ||||||||||||||||||||||||||||||||
| Net treasury stock issued for share-based awards | $ (12) | (21) | 10 | (1) | |||||||||||||||||||||||||||||||
| UAL contribution related to stock plans | 2 | 2 | |||||||||||||||||||||||||||||||||
| Reclassification of stranded tax effects | 118 | 118 | (118) | (118) | |||||||||||||||||||||||||||||||
| Other | $ (15) | (15) | |||||||||||||||||||||||||||||||||
| Balance (in shares) at Dec. 31, 2017 | 286,973,195 | [9] | 1,000 | [10] | 287,000,000 | ||||||||||||||||||||||||||||||
| Balance at Dec. 31, 2017 | $ 8,734 | [9] | $ 8,696 | [10] | $ 3 | 6,098 | 1,787 | (769) | 4,549 | 8,146 | (1,147) | (1,147) | (90) | ||||||||||||||||||||||
| Net income | 2,129 | 2,131 | 2,129 | 2,131 | |||||||||||||||||||||||||||||||
| Other comprehensive income (loss) | 338 | 338 | 338 | 338 | |||||||||||||||||||||||||||||||
| Stock-settled share-based compensation | $ 60 | 60 | 60 | 60 | |||||||||||||||||||||||||||||||
| Dividend to UAL | (1,249) | (1,249) | |||||||||||||||||||||||||||||||||
| Proceeds from exercise of stock options / net treasury stock issued for share-based awards (in shares) | 400,000 | ||||||||||||||||||||||||||||||||||
| Repurchases of common stock (in shares) | (17,500,000) | (17,500,000) | |||||||||||||||||||||||||||||||||
| Repurchases of common stock | $ (1,250) | (1,250) | |||||||||||||||||||||||||||||||||
| Net treasury stock issued for share-based awards | $ (16) | (38) | 26 | (4) | |||||||||||||||||||||||||||||||
| Other | $ (19) | (5) | 6 | (20) | |||||||||||||||||||||||||||||||
| Balance (in shares) at Dec. 31, 2018 | 269,914,769 | 1,000 | 269,900,000 | ||||||||||||||||||||||||||||||||
| Balance at Dec. 31, 2018 | $ 9,995 | $ 9,957 | $ 3 | $ 6,120 | $ 598 | $ (1,993) | $ 6,668 | $ 10,272 | $ (803) | $ (803) | $ (110) | ||||||||||||||||||||||||
| |||||||||||||||||||||||||||||||||||
| X | ||||||||||
- Definition Capital contributions from parent No definition available.
|
| X | ||||||||||
- Definition Capital Contributions To Parent No definition available.
|
| X | ||||||||||
- Definition Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings, Tax Effect No definition available.
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| X | ||||||||||
- Definition Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount after tax and reclassification adjustments of other comprehensive income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Value of stock issued as a result of the exercise of stock options. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Equity impact of the value of treasury stock (units) reissued during the period, excluding reissuance of shares (units) held in treasury used to satisfy equity-based compensation obligations exercised by the holders of such rights. Upon reissuance of shares (units) from treasury, either the common or preferred stock (unit) reissued is outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition This element represents movements included in the statement of changes in stockholders' equity which are not separately disclosed or provided for elsewhere in the taxonomy. No definition available.
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| X | ||||||||||
- Definition Amount of decrease of par value, additional paid in capital (APIC) and retained earnings of common and preferred stock retired from treasury when treasury stock is accounted for under the cost method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Number of shares that have been repurchased during the period and are being held in treasury. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Significant Accounting Policies |
12 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| Accounting Policies [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Significant Accounting Policies | SIGNIFICANT ACCOUNTING POLICIES
Passenger tickets and related ancillary services sold by the Company for mainline and regional flights are purchased primarily via credit card transactions, with payments collected by the Company in advance of the performance of related services. The Company initially records ticket sales in its Advance ticket sales liability, deferring revenue recognition until the travel occurs. For travel that has more than one flight segment, the Company deems each segment as a separate performance obligation and recognizes revenue for each segment as travel occurs. Tickets sold by other airlines where the Company provides the transportation are recognized as passenger revenue at the estimated value to be billed to the other airline when travel is provided. Differences between amounts billed and the actual amounts may be rejected and rebilled or written off if the amount recorded was different from the original estimate. When necessary, the Company records a reserve against its billings and payables with other airlines based on historical experience. The Company sells certain tickets with connecting flights with one or more segments operated by its other airline partners. For segments operated by its other airline partners, the Company has determined that it is acting as an agent on behalf of the other airlines as they are responsible for their portion of the contract (i.e. transportation of the passenger). The Company, as the agent, recognizes revenue within Other operating revenue at the time of the travel for the net amount representing commission to be retained by the Company for any segments flown by other airlines. Refundable tickets expire after one year from the date of issuance. Non-refundable tickets generally expire on the date of the intended travel, unless the date is extended by notification from the customer on or before the intended travel date. The Company records breakage revenue on the travel date for its estimate of tickets that will expire unused. To determine breakage, the Company uses its historical experience with refundable and nonrefundable expired tickets and other facts, such as recent aging trends, program changes and modifications that could affect the ultimate expiration patterns of tickets. Fees charged in association with changes or extensions to non-refundable tickets are considered part of the Company's passenger travel obligation. As such, those fees are deferred at the time of collection and recognized at the time the travel is provided. United initially capitalizes the costs of selling airline travel tickets and then recognizes those costs as Distribution expense at the time of travel. Passenger ticket costs include credit card fees, travel agency and other commissions paid, as well as global distribution systems booking fees. Advance Ticket Sales. Advance ticket sales represent the Company's liability to provide air transportation in the future. In the years ended December 31, 2018 and 2017, the Company recognized approximately $3.1 billion and $2.9 billion, respectively, of passenger revenue for tickets that were included in Advance ticket sales at the beginning of those periods. All tickets sold at any given point of time have travel dates extending up to twelve months. As a result, the balance of the Company's Advance ticket sales liability represents activity that will be recognized in the next twelve months.
The Company deploys its aircraft across its route network through a single route scheduling system to maximize its value. When making resource allocation decisions, the Company's chief operating decision maker evaluates flight profitability data, which considers aircraft type and route economics. The Company's chief operating decision maker makes resource allocation decisions to maximize the Company's consolidated financial results. Managing the Company as one segment allows management the opportunity to maximize the value of its route network. The Company's operating revenue by principal geographic region (as defined by the U.S. Department of Transportation) for the years ended December 31 is presented in the table below (in millions):
(1) Amounts adjusted due to the adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606). See (u) below for additional information. The Company attributes revenue among the geographic areas based upon the origin and destination of each flight segment. The Company's operations involve an insignificant level of dedicated revenue-producing assets in geographic regions as the overwhelming majority of the Company's revenue-producing assets (primarily U.S. registered aircraft) can be deployed in any of its geographic regions. Ancillary Fees. The Company charges fees, separately from ticket sales, for certain ancillary services that are directly related to passengers' travel, such as ticket change fees, baggage fees, inflight amenities fees, and other ticket-related fees. These ancillary fees are part of the travel performance obligation and, as such, are recognized as passenger revenue when the travel occurs. The Company recorded $2.2 billion, $2.0 billion, and $1.9 billion of ancillary fees within passenger revenue in the years ended December 31, 2018, 2017 and 2016 respectively.
Miles Earned in Conjunction with Travel. When frequent flyers earn miles for flights, the Company recognizes a portion of the ticket sales as revenue when the travel occurs and defers a portion of the ticket sale representing the value of the related miles as a separate performance obligation. The Company determines the estimated selling price of travel and miles as if each element is sold on a separate basis. The total consideration from each ticket sale is then allocated to each of these elements, individually, on a pro-rata basis. At the time of travel, the Company records the portion allocated to the miles to Frequent flyer deferred revenue on the Company's consolidated balance sheet and subsequently recognizes it into revenue when miles are redeemed for air travel and non-air travel awards. The Company's estimated selling price of miles is based on an equivalent ticket value less breakage, which incorporates the expected redemption of miles, as the best estimate of selling price for these miles. The equivalent ticket value is based on the prior 12 months' weighted average equivalent ticket value of similar fares as those used to settle award redemptions while taking into consideration such factors as redemption pattern, cabin class, loyalty status and geographic region. The estimated selling price of miles is adjusted by breakage that considers a number of factors, including redemption patterns of various customer groups. The Company reviews its breakage estimates annually based upon the latest available information regarding redemption and expiration patterns. The Company's estimate of the expected expiration of miles requires significant management judgment. Current and future changes to expiration assumptions or to the expiration policy, or to program rules and program redemption opportunities, may result in material changes to the deferred revenue balance as well as recognized revenues from the program. For the portion of the outstanding miles that we estimate will not be redeemed, we recognize the associated value proportionally as the remaining miles are redeemed. Co-Brand Agreement. United has a significant contract (the "Co-Brand Agreement") to sell MileagePlus miles to its co-branded credit card partner Chase Bank USA, N.A. ("Chase"). Chase awards miles to MileagePlus members based on their credit card activity. United identified the following significant separately identifiable performance obligations in the Co-Brand Agreement:
We account for all the payments received (including monthly and one-time payments) under the Co-Brand Agreement by allocating them to the separately identifiable performance obligations. The fair value of the separately identifiable performance obligations is determined using management's estimated selling price of each component. The objective of using the estimated selling price based methodology is to determine the price at which we would transact a sale if the product or service were sold on a stand-alone basis. Accordingly, we determine our best estimate of selling price by considering multiple inputs and methods including, but not limited to, discounted cash flows, brand value, volume discounts, published selling prices, number of miles awarded and number of miles redeemed. The Company estimated the selling prices and volumes over the term of the Co-Brand Agreement in order to determine the allocation of proceeds to each of the components to be delivered. We also evaluate volumes on an annual basis, which may result in a change in the allocation of the estimated consideration from the Co-Brand Agreement on a prospective basis. Frequent flyer deferred revenue. Miles in MileagePlus members' accounts are combined into one homogeneous pool and are thus not separately identifiable, for award redemption purposes, between miles earned in the current period and those in their beginning balance. Of the miles expected to be redeemed, the Company expects the majority of these miles to be redeemed within two years. The table below presents a roll forward of Frequent flyer deferred revenue (in millions):
In the year ended December 31, 2018, 2017 and 2016, the Company recognized, in Other operating revenue, $2.0 billion, $1.8 billion and $1.7 billion, respectively, related to the marketing, advertising, non-travel miles redeemed (net of related costs) and other travel-related benefits of the mileage revenue associated with our various partner agreements including, but not limited to, our Chase co-brand agreement. The portion related to the MileagePlus miles awarded of the total amounts received is deferred and presented in the table above as an increase to the frequent flyer liability.
Restricted cash primarily includes cash collateral for letters of credit and collateral associated with obligations for facility leases and other insurance-related obligations. Restricted cash is classified as short-term or long-term in the consolidated balance sheets based on the expected timing of return of the assets to the Company. The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the consolidated balance sheets that sum to the total of the same such amounts shown in the statements of consolidated cash flows (in millions):
Depreciation and amortization of owned depreciable assets is based on the straight-line method over the assets' estimated useful lives. Leasehold improvements are amortized over the remaining term of the lease, including estimated facility renewal options when renewal is reasonably assured at key airports, or the estimated useful life of the related asset, whichever is less. Properties under capital leases are amortized on the straight-line method over the life of the lease or, in the case of certain aircraft, over their estimated useful lives, whichever is shorter. Amortization of capital lease assets is included in depreciation and amortization expense. The estimated useful lives of property and equipment are as follows:
As of December 31, 2018 and 2017, the Company had a carrying value of computer software of $359 million and $345 million, respectively. For the years ended December 31, 2018, 2017 and 2016, the Company's depreciation expense related to computer software was $122 million, $117 million and $108 million, respectively. Aircraft and aircraft spare parts were assumed to have residual values of approximately 10% of original cost, and other categories of property and equipment were assumed to have no residual value.
The Company adopted Accounting Standards Update No. 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost (the "New Retirement Standard"), effective January 1, 2018 using the full-retrospective method. The New Retirement Standard requires employers to present the service cost component of the net periodic benefit cost in the same income statement line item as other employee compensation costs arising from services rendered during the period. The other components of net benefit cost, including interest cost, expected return on plan assets, amortization of prior service cost/credit and actuarial gain/loss, and settlement and curtailment effects, are to be presented outside of any subtotal of operating income. The Company elected to apply the practical expedient and use the amounts disclosed in Note 8 to the financial statements included in Part II, Item 8 of the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2017 as the estimation basis for applying the retrospective presentation requirements of the standard. The New Revenue Standard and the New Retirement Standard had the same impact on the financial statements of United as they had on the financial statements of UAL. The tables below present the impact of the adoption of the New Revenue Standard and the New Retirement Standard on select accounts and captions of UAL's statements of consolidated operations for the twelve months ended December 31, 2017 and 2016 (in millions, except per share amounts) and the impact on UAL's balance sheet accounts and captions as of December 31, 2017 (in millions):
The Company adopted Accounting Standards Update No. 2016-01, Financial Instruments—Overall (Subtopic 825-10) effective January 1, 2018. This standard made several changes, including the elimination of the available-for-sale classification of equity investments, and requires equity investments with readily determinable fair values to be measured at fair value with changes in fair value recognized in earnings. The Company reclassified to retained earnings $6 million of unrealized loss, net of tax, on the Company's investment in Azul, S.A. ("Azul") which was previously classified as an available-for-sale security. See Notes 6 and 9 to the financial statements included in this Part II, Item 8 for additional information. In June 2016, the FASB issued Accounting Standards Update No. 2016-13, Financial Instruments—Credit Losses ("ASU 2016-13"). The main objective is to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. The amendments in this update replace the incurred loss methodology with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to calculate credit loss estimates. For trade receivables, loans and held-to-maturity debt securities, entities will be required to estimate lifetime expected credit losses. For available-for-sale debt securities, entities will be required to recognize an allowance for credit losses rather than a reduction to the carrying value of the asset. The amendments are effective for public business entities for fiscal years and interim periods beginning after December 15, 2019. The Company is evaluating the impact the adoption of ASU 2016-13 will have on its consolidated financial statements and believes that it will not have a material impact on its consolidated financial statements. In 2016, the FASB amended the FASB Accounting Standards Codification and created a new Topic 842, Leases (the "New Lease Standard"). The guidance requires lessees to recognize a right-of-use asset and a lease liability for all leases (with the exception of short-term leases) at the commencement date and recognize expenses on their income statements similar to the current Topic 840, Leases ("Topic 840"). The New Lease Standard is effective for fiscal years and interim periods beginning after December 15, 2018. The Company adopted this standard on January 1, 2019 using a modified retrospective approach for all leases existing at or commencing after the date of initial application and utilizing certain practical expedients. The adoption of the New Lease Standard is expected to impact our reported results as shown in the tables below (in millions, except per share amounts):
(a) Finance leases, under the New Lease Standard, are the equivalent of capital leases under Topic 840. The adoption of the New Lease Standard primarily resulted in the recording of assets and obligations of our operating leases on our consolidated balance sheets. Certain amounts recorded for prepaid and accrued rent associated with historical operating leases were reclassified to the newly captioned Operating lease assets in the consolidated balance sheets. Also, certain leases designated under Topic 840 as owned assets and capitalized finance leases will not be considered assets under the New Lease Standard and will be removed from the consolidated balance sheets, along with the related capital lease liability.
The expense for leases under the New Lease Standard will continue to be classified in their historical income statement captions (primarily in Aircraft rent, Landing fees and other rent and Regional capacity purchase in our statements of consolidated operations). The adoption of the New Lease Standard also resulted in the recharacterization of certain leases from capital leases under Topic 840 to operating leases under the New Lease Standard. This change will result in less depreciation and amortization and interest expense associated with capital leases offset by higher lease expense associated with operating leases. The change is associated with leases of aircraft under certain CPAs and certain airport facilities. The reduction in capitalized interest is also associated with the same airport facilities. |
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- Definition The entire disclosure for all significant accounting policies of the reporting entity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Goodwill and Other Intangible Assets |
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| Goodwill and Intangible Assets Disclosure [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Goodwill and Other Intangible Assets | GOODWILL AND OTHER INTANGIBLE ASSETS The following table presents information about the Company's goodwill and other intangible assets at December 31 (in millions):
Amortization expense in 2018, 2017 and 2016 was $67 million, $79 million and $90 million, respectively. Projected amortization expense in 2019, 2020, 2021, 2022 and 2023 is $61 million, $55 million, $50 million, $40 million and $37 million, respectively. See Note 14 of this report for additional information related to impairment of intangible assets. |
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- Definition The entire disclosure for the aggregate amount of goodwill and a description of intangible assets, which may include (a) for amortizable intangible assets (also referred to as finite-lived intangible assets), the carrying amount, the amount of any significant residual value, and the weighted-average amortization period, (b) for intangible assets not subject to amortization (also referred to as indefinite-lived intangible assets), the carrying amount, and (c) the amount of research and development assets acquired and written off in the period, including the line item in the income statement in which the amounts written off are aggregated, if not readily apparent from the income statement. Also discloses (a) for amortizable intangibles assets in total and by major class, the gross carrying amount and accumulated amortization, the total amortization expense for the period, and the estimated aggregate amortization expense for each of the five succeeding fiscal years, (b) for intangible assets not subject to amortization the carrying amount in total and by major class, and (c) for goodwill, in total and for each reportable segment, the changes in the carrying amount of goodwill during the period (including the aggregate amount of goodwill acquired, the aggregate amount of impairment losses recognized, and the amount of goodwill included in the gain (loss) on disposal of a reporting unit). If any part of goodwill has not been allocated to a reportable segment, discloses the unallocated amount and the reasons for not allocating. For each impairment loss recognized related to an intangible asset (excluding goodwill), discloses: (a) a description of the impaired intangible asset and the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method for determining fair value, (c) the caption in the income statement or the statement of activities in which the impairment loss is aggregated, and (d) the segment in which the impaired intangible asset is reported. For each goodwill impairment loss recognized, discloses: (a) a description of the facts and circumstances leading to the impairment, (b) the amount of the impairment loss and the method of determining the fair value of the associated reporting unit, and (c) if a recognized impairment loss is an estimate not finalized and the reasons why the estimate is not final. May also disclose the nature and amount of any significant adjustments made to a previous estimate of an impairment loss. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Common Stockholders' Equity and Preferred Securities |
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| Equity [Abstract] | |
| Common Stockholders' Equity and Preferred Securities | COMMON STOCKHOLDERS' EQUITY AND PREFERRED SECURITIES In 2018, UAL repurchased approximately 17.5 million shares of UAL common stock for $1.2 billion. In December 2017, UAL's Board of Directors authorized a $3.0 billion share repurchase program to acquire UAL's common stock. As of December 31, 2018, the Company had approximately $1.8 billion remaining to purchase shares under its share repurchase program. UAL may repurchase shares through the open market, privately negotiated transactions, block trades or accelerated share repurchase transactions from time to time in accordance with applicable securities laws. UAL may repurchase shares of UAL common stock subject to prevailing market conditions, and may discontinue such repurchases at any time. See Part II, Item 5, Market for registrant's common equity, related stockholder matters and issuer purchases of equity securities, of this report for additional information. At December 31, 2018, approximately 10 million shares of UAL's common stock were reserved for future issuance related to the issuance of equity-based awards under the Company's incentive compensation plans. As of December 31, 2018, UAL had two shares of junior preferred stock (par value $0.01 per share) outstanding. In addition, UAL is authorized to issue 250 million shares of preferred stock (without par value) under UAL's amended and restated certificate of incorporation. |
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- Definition The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Earnings Per Share |
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| Earnings Per Share | EARNINGS PER SHARE The computations of UAL's basic and diluted earnings per share are set forth below for the years ended December 31 (in millions, except per share amounts):
(a) Amounts adjusted due to the adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606). See Note 1 to the financial statements contained in Part II, Item 8 of this report for additional information. The number of antidilutive securities excluded from the computation of diluted earnings per share amounts was not material. |
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- Definition The entire disclosure for earnings per share. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Share-Based Compensation Plans |
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| Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Share-Based Compensation Plans | SHARE-BASED COMPENSATION PLANS UAL maintains several share-based compensation plans. These plans provide for grants of non-qualified stock options, incentive stock options (within the meaning of Section 422 of the Internal Revenue Code of 1986), stock appreciation rights, restricted shares, RSUs, performance compensation awards, performance units, cash incentive awards, other equity-based and equity-related awards, and dividends and dividend equivalents. All awards are recorded as either equity or a liability in the Company's consolidated balance sheets. The share-based compensation expense is recorded in salaries and related costs. During 2018, UAL granted share-based compensation awards pursuant to the United Continental Holdings, Inc. 2017 Incentive Compensation Plan. These share-based compensation awards included approximately 1.8 million RSUs consisting of 1.1 million time-vested RSUs and 0.7 million performance-based RSUs. The time-vested RSUs vest pro-rata, a majority of which vest on February 28th of each year over a three-year period from the date of grant. These RSUs are generally equity awards settled in stock for domestic employees and liability awards settled in cash for international employees. The cash payments are based on the 20-day average closing price of UAL common stock immediately prior to the vesting date. The performance-based RSUs vest based on the Company's relative improvement in pre-tax margin compared to a group of airline industry peers for the three years ending December 31, 2020. If the performance condition is achieved, cash payments will be made after the end of the performance period based on the 20-day average closing price of UAL common stock immediately prior to the vesting date and based on the level, if any, of the performance goal achieved. The Company accounts for the performance-based RSUs as liability awards. The following table provides information related to UAL's share-based compensation plan cost for the years ended December 31 (in millions):
The table below summarizes UAL's unearned compensation and weighted-average remaining period to recognize costs for all outstanding share-based awards that are probable of being achieved as of December 31, 2018 (in millions, except as noted):
RSUs and Restricted Stock. All performance-based RSUs, as well as a portion of the outstanding time-vested RSUs, will be settled in cash. As of December 31, 2018, UAL had recorded a liability of $51 million related to its RSUs. UAL paid $28 million, $50 million and $69 million related to its RSUs during 2018, 2017 and 2016, respectively. The table below summarizes UAL's RSUs and restricted stock activity for the years ended December 31 (shares in millions):
The fair value of RSUs and restricted stock that vested in 2018, 2017 and 2016 was $70 million, $76 million and $80 million, respectively. The fair value of the restricted stock and the stock-settled RSUs was based upon the UAL common stock price on the date of grant. These awards are accounted for as equity awards. The fair value of the cash-settled RSUs was based on the UAL common stock price as of the last day preceding the settlement date. These awards are accounted for as liability awards. Restricted stock vesting and the recognition of the expense is similar to the stock option vesting described below. Stock Options. During 2018, UAL did not grant any stock option awards. In 2017, UAL granted approximately 36,000 stock options with exercise prices equal to the fair market value of UAL's common stock on the date of grant with a weighted-average exercise price of $77.56 and a weighted-average grant date fair value of approximately $0.7 million. In 2016, UAL granted approximately 0.1 million stock options with exercise prices equal to the fair market value of UAL's common stock on the date of grant and an additional approximately 0.3 million stock options with exercise prices at a 25% premium of the grant date fair market value resulting in a weighted-average exercise price of $56.19 and a weighted-average grant date fair value of approximately $2.3 million. Expense related to each portion of an option grant is recognized on a straight-line basis over the specific vesting period for those options. The Company determined the grant date fair value of stock options using a Black-Scholes option pricing model, which requires the use of several assumptions. The risk-free interest rate is based on the U.S. treasury yield curve in effect for the expected term of the option at the time of grant. The dividend yield on UAL's common stock was assumed to be zero since UAL did not have any plans to pay dividends at the time of the option grants. The volatility assumptions were based upon historical volatilities of UAL using daily stock price returns equivalent to the expected term of the option. The expected term of the options was determined based upon a simplified assumption that the option will be exercised evenly from vesting to expiration due to the Company's lack of relevant historical data related to stock options. As of December 31, 2018, there were approximately 0.4 million outstanding stock option awards, 0.2 million of which were exercisable, with weighted-average exercise prices of $55.62 and $47.07, respectively, intrinsic values of $12 million and $6 million, respectively, and weighted-average remaining contractual lives (in years) of 5.8 and 3.8, respectively. |
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- Definition The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Accumulated Other Comprehensive Income (Loss) |
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| Equity [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Accumulated Other Comprehensive Income (Loss) | ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) The tables below present the components of the Company's AOCI, net of tax (in millions):
(a) Prior service credits decreased by $3 million, $0 million and increased by $30 million and actuarial losses decreased by approximately $380 million, and increased $306 million and $560 million for 2018, 2017 and 2016, respectively. (b) This amount represents the reclassification from AOCI to RE of the stranded tax effects resulting from the enactment of the Tax Cuts and Jobs Act (the "Tax Act"). (c) This AOCI component is included in the computation of net periodic pension and other postretirement costs (see Note 8 of this report for additional information). |
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- Definition The entire disclosure for comprehensive income, which includes, but is not limited to, 1) the amount of income tax expense or benefit allocated to each component of other comprehensive income, including reclassification adjustments, 2) the reclassification adjustments for each classification of other comprehensive income and 3) the ending accumulated balances for each component of comprehensive income. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Income Taxes |
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| Income Tax Disclosure [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Income Taxes | INCOME TAXES The income tax provision (benefit) differed from amounts computed at the statutory federal income tax rate and consisted of the following significant components, as follows (in millions):
(a) Amounts adjusted due to the adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606). See Note 1 to the financial statements contained in Part II, Item 8 of this report for additional information. (b) Prior to the release of the deferred income tax valuation allowance in the third quarter of 2015, the Company recorded approximately $465 million of valuation allowance adjustments in AOCI. Subsequent to the release of the deferred income tax valuation allowance in 2015, the $465 million debit remained within AOCI, of which $180 million related to losses on fuel hedges designated for hedge accounting and $285 million related to pension and other postretirement liabilities. Accounting rules required the adjustments to remain in AOCI as long as the Company had fuel derivatives designated for cash flow hedge accounting and the Company continues to provide pension and postretirement benefits. In 2016, the Company settled all of its fuel hedges and has not entered into any new fuel derivative contracts for hedge accounting. Accordingly, the Company reclassified the $180 million to income tax expense in 2016. The Company's effective tax rate for the year ended December 31, 2018 differed from the federal statutory rate of 21% due to a blend of federal, state and foreign taxes as well as the impact of certain nondeductible items. On December 22, 2017, Congress enacted the Tax Act, which made significant changes to U.S. federal income tax laws, including reducing the corporate rate from 35% to 21% effective January 1, 2018. In December 2017, the SEC issued Staff Accounting Bulletin No. 118 ("SAB 118"), which allowed the Company to record provisional amounts related to the impact of the Tax Act and to adjust those amounts during a measurement period not to extend more than one year from the date of enactment. Based on our current interpretation of the Tax Act and published Treasury and Internal Revenue Service ("IRS") guidance as of December 31, 2018, the Company's accounting for the impacts of the Tax Act is complete and the Company has not recorded any material adjustments to the provisional amounts under SAB 118. In 2018, we recorded an income tax benefit for the one-time transition tax of $4 million and have completed the re-measurement of our net deferred tax balances. The Tax Act included a Global Intangible Low-Taxed Income ("GILTI") provision which introduced a new tax on foreign income in excess of a deemed return on tangible business property of foreign subsidiaries. The GILTI provisions of the Tax Act became effective for the Company during 2018 and we elected to account for it in the period incurred (the "period cost method"). Temporary differences and carryforwards that give rise to deferred tax assets and liabilities at December 31, 2018 and 2017 were as follows (in millions):
United and its domestic consolidated subsidiaries file a consolidated federal income tax return with UAL. Under an intercompany tax allocation policy, United and its subsidiaries compute, record and pay UAL for their own tax liability as if they were separate companies filing separate returns. In determining their own tax liabilities, United and each of its subsidiaries take into account all tax credits or benefits generated and utilized as separate companies and they are each compensated for the aforementioned tax benefits only if they would be able to use those benefits on a separate company basis. The Company's federal and state NOL carryforwards relate to prior years' NOLs, which may be used to reduce tax liabilities in future years. These tax benefits are mostly attributable to federal pre-tax NOL carryforwards of $1.6 billion for UAL. If not utilized these federal pre-tax NOLs will expire as follows (in billions): $0.6 in 2030, $1.0 thereafter. In addition, for UAL the majority of tax benefits of the state NOLs of $83 million will expire over a five to twenty year period. We have recorded a $48 million valuation allowance against these state NOLs. The Company's unrecognized tax benefits related to uncertain tax positions were $39 million, $21 million and $74 million at December 31, 2018, 2017 and 2016, respectively. Included in the ending balance at December 31, 2018 is $39 million that would affect the Company's effective tax rate if recognized. The changes in unrecognized tax benefits relating to settlements with taxing authorities, unrecognized tax benefits as a result of tax positions taken during a prior period and unrecognized tax benefits relating from a lapse of the statute of limitations were immaterial during 2018, 2017 and 2016. The Company does not expect significant increases or decreases in their unrecognized tax benefits within the next 12 months. There are no material amounts included in the balance at December 31, 2018 for tax positions for which the ultimate deductibility is highly certain but for which there is uncertainty about the timing of such deductibility. The Company's federal income tax returns for tax years after 2002 remain subject to examination by the IRS and state taxing jurisdictions. Currently, there are no ongoing examinations of the Company's prior year tax returns being conducted by the IRS. |
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- References No definition available.
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- Definition The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Pension and Other Postretirement Plans |
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| Retirement Benefits [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Pension and Other Postretirement Plans | PENSION AND OTHER POSTRETIREMENT PLANS The following summarizes the significant pension and other postretirement plans of United: Pension Plans. United maintains two primary defined benefit pension plans, one covering certain pilot employees and another covering certain U.S. non-pilot employees. Each of these plans provide benefits based on a combination of years of benefit accruals service and an employee's final average compensation. Additional benefit accruals are frozen under the plan covering certain pilot employees and management and administrative employees. Benefit accruals for certain non-pilot employees continue. United maintains additional defined benefit pension plans, which cover certain international employees. Other Postretirement Plans. United maintains postretirement medical programs which provide medical benefits to certain retirees and eligible dependents, as well as life insurance benefits to certain retirees participating in the plan. Benefits provided are subject to applicable contributions, co-payments, deductibles and other limits as described in the specific plan documentation. Actuarial assumption changes are reflected as a component of the net actuarial loss/(gain) during 2018 and 2017. The 2018 actuarial gains were mainly related to an increase in the discount rate applied in 2018 compared to 2017. These amounts will be amortized over the average remaining service life of the covered active employees or the average life expectancy of inactive participants. The impacts on 2018 and 2017 pension and retiree medical expense are presented below. The following tables set forth the reconciliation of the beginning and ending balances of the benefit obligation and plan assets, the funded status and the amounts recognized in these financial statements for the defined benefit and other postretirement plans (in millions):
The following information relates to all pension plans with an accumulated benefit obligation and a projected benefit obligation in excess of plan assets at December 31 (in millions):
Net periodic benefit cost for the years ended December 31 included the following components (in millions):
Service cost is recorded in Salaries and related costs on the statement of consolidated operations. All other components of net periodic benefit costs are recorded in Miscellaneous, net on the statement of consolidated operations. See Note 14 of this report for additional information related to the curtailment gain recorded in 2016. The assumptions used for the benefit plans were as follows:
The Company used the Society of Actuaries' 2014 mortality tables, modified to reflect the Social Security Administration Trustee's Report on current projections regarding expected longevity improvements. The Company selected the 2018 discount rate for substantially all of its plans by using a hypothetical portfolio of high quality bonds at December 31, 2018, that would provide the necessary cash flows to match projected benefit payments. We develop our expected long-term rate of return assumption for our defined benefit plans based on historical experience and by evaluating input from the trustee managing the plans' assets. Our expected long-term rate of return on plan assets for these plans is based on a target allocation of assets, which is based on our goal of earning the highest rate of return while maintaining risk at acceptable levels. The plans strive to have assets sufficiently diversified so that adverse or unexpected results from one security class will not have an unduly detrimental impact on the entire portfolio. Plan fiduciaries regularly review our actual asset allocation and the pension plans' investments are periodically rebalanced to our targeted allocation when considered appropriate. United's plan assets are allocated within the following guidelines:
One-hundred percent of other postretirement plan assets are invested in a deposit administration fund. A one percentage point decrease in the weighted average discount rate would increase the Company's postretirement benefit liability by approximately $139 million and increase the estimated 2018 benefits expense by approximately $10 million. Fair Value Information. Accounting standards require us to use valuation techniques to measure fair value that maximize the use of observable inputs and minimize the use of unobservable inputs. These inputs are prioritized as follows:
Assets and liabilities measured at fair value are based on the valuation techniques identified in the tables below. The valuation techniques are as follows: (a) Market approach. Prices and other relevant information generated by market transactions involving identical or comparable assets and liabilities; and (b) Income approach. Techniques to convert future amounts to a single current value based on market expectations (including present value techniques, option-pricing and excess earnings models). The following tables present information about United's pension and other postretirement plan assets at December 31, (in millions):
(a) In accordance with the relevant accounting standards, certain investments that are measured at fair value using the net asset value ("NAV") per share (or its equivalent) have not been classified in the fair value hierarchy. These investments are commingled funds that invest in fixed-income instruments including bonds, debt securities, and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. Redemption periods for these investments range from daily to semiannually. Equity and Fixed-Income. Equities include investments in both developed market and emerging market equity securities. Fixed-income includes primarily U.S. and non-U.S. government fixed-income securities and U.S. and non-U.S. corporate fixed-income securities. Deposit Administration Fund. This investment is a stable value investment product structured to provide investment income. Alternatives. Alternative investments consist primarily of investments in hedge funds, real estate and private equity interests. Other investments. Other investments consist of cash, insurance contracts and other funds. The reconciliation of United's defined benefit plan assets measured at fair value using unobservable inputs (Level 3) for the years ended December 31, 2018 and 2017 is as follows (in millions):
Funding requirements for tax-qualified defined benefit pension plans are determined by government regulations. United's contributions reflected above have satisfied its required contributions through the 2018 calendar year. In 2019, employer anticipated contributions to all of United's pension and postretirement plans are at least $318 million and approximately $95 million, respectively. The estimated future benefit payments, net of expected participant contributions, in United's pension plans and other postretirement benefit plans as of December 31, 2018 are as follows (in millions):
Defined Contribution Plans Depending upon the employee group, employer contributions consist of matching contributions and/or non-elective employer contributions. United's employer contribution percentages vary from 1% to 16% of eligible earnings depending on the terms of each plan. United recorded expenses for its defined contribution plans of $693 million, $656 million and $592 million in the years ended December 31, 2018, 2017 and 2016, respectively. Multi-Employer Plans United's participation in the IAM National Pension Plan ("IAM Plan") for the annual period ended December 31, 2018 is outlined in the table below. There have been no significant changes that affect the comparability of 2018 and 2017 contributions. The risks of participating in these multi-employer plans are different from single-employer plans, as United may be subject to additional risks that others do not meet their obligations, which in certain circumstances could revert to United. The IAM Plan reported $435 million in employers' contributions for the year ended December 31, 2017. For 2017, the Company's contributions to the IAM Plan represented more than 5% of total contributions to the IAM Plan. The 2018 information is not available as Form 5500 is not final for the plan year.
Profit Sharing Substantially all employees participate in profit sharing based on a percentage of pre-tax earnings, excluding special charges, profit sharing expense and share-based compensation. Profit sharing percentages range from 5% to 20% depending on the work group, and in some cases profit sharing percentages vary above and below certain pre-tax margin thresholds. Eligible U.S. co-workers in each participating work group receive a profit sharing payout using a formula based on the ratio of each qualified co-worker's annual eligible earnings to the eligible earnings of all qualified co-workers in all domestic work groups. Eligible non-U.S. co-workers receive profit sharing based on the calculation under the U.S. profit sharing plan for management and administrative employees. The Company recorded profit sharing and related payroll tax expense of $334 million, $349 million and $628 million in 2018, 2017 and 2016, respectively. Profit sharing expense is recorded as a component of Salaries and related costs in the Company's statements of consolidated operations. |
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- References No definition available.
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- Definition The entire disclosure for pension and other postretirement benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Investments and Fair Value Measurements |
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| Fair Value Disclosures [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Investments and Fair Value Measurements | INVESTMENTS AND FAIR VALUE MEASUREMENTS Fair Value Information. Accounting standards require us to use valuation techniques to measure fair value that maximize the use of observable inputs and minimize the use of unobservable inputs. These inputs are described in Note 8 of this report. The table below presents disclosures about the fair value of financial assets and liabilities measured at fair value on a recurring basis in the Company's financial statements as of December 31 (in millions):
Available-for-sale investment maturities - The short-term investments shown in the table above are classified as available-for-sale, with the exception of investments measured at NAV. As of December 31, 2018, asset-backed securities have remaining maturities of less than one year to approximately 16 years, corporate debt securities have remaining maturities of less than one year to approximately three years and CDARS have maturities of less than one year. U.S. government and other securities have maturities of less than one year to approximately two years. The EETC securities mature in 2019. Restricted cash - Restricted cash primarily includes cash collateral for letters of credit and collateral associated with obligations for facility leases and other insurance-related obligations. Equity securities - Equity securities represent United's investment in Azul. In 2018, the Company invested $138 million in Azul thus increasing its preferred equity stake in Azul to approximately 8% (representing approximately 2% of the total capital stock of Azul). The Company recognizes changes to the fair value of its equity investment in Azul in Miscellaneous, net in its statements of consolidated operations. Synergy Term Loan - On November 29, 2018, United, as lender, entered into a Term Loan Agreement (the "Synergy Loan Agreement") with affiliates of Synergy Aerospace Corporation ("Synergy"), as borrower and guarantor, respectively, and, pursuant to the Synergy Loan Agreement, on November 30, 2018, United provided a $456 million term loan to Synergy (the "Synergy Term Loan"), secured by a pledge of borrower's equity, as well as Synergy's 516 million shares of common stock of AVH, the parent company of Avianca (equivalent to 64.5 million American Depositary Receipts ("ADRs"), the class of AVH securities that trades on the New York Stock Exchange ("NYSE")). Pursuant to the Synergy Loan Agreement, the Synergy Term Loan is due and payable in five annual installments beginning on November 30, 2021, to be repaid in full on November 30, 2025 (a portion of which is subject to extension in limited circumstances). Subject to the satisfaction of collateral coverage thresholds, minimum share price levels and certain other conditions, Synergy may repay United in shares of AVH common stock, at market value, in an amount up to 25 percent of any principal installment, or with cash from the sale of Synergy's shares of AVH stock. The Synergy Term Loan bears interest at an annual rate of 3 percent per annum, payable quarterly in arrears. United also obtained an option to acquire, on a gross or net basis and at a fixed price, up to 77.4 million shares of AVH common stock from Synergy (the "AVH Call Options"), and agreed with Synergy to share in any increase in value of the remaining 438.6 million shares of Synergy's AVH common stock within certain price ranges (the "AVH Share Appreciation Rights"). Until the third anniversary of funding, Synergy has the option to capitalize interest that would have been due, adding it to the outstanding principal balance of the Synergy Term Loan. Pursuant to the Synergy Loan Agreement, Synergy has agreed to certain financial and non-financial covenants, as well as customary events of default. In connection with funding the Synergy Loan Agreement, on November 29, 2018, United also entered into an agreement with AVH's significant minority shareholder, Kingsland Holdings Limited ("Kingsland"), pursuant to which, in return for Kingsland's pledge of its 144.8 million shares of AVH common stock (equivalent to 18.1 million ADRs) and its consent to Synergy's pledge of its AVH common stock to United under the Synergy Loan Agreement, United (1) granted to Kingsland the right to put its shares of AVH common stock to United at market price on the fifth anniversary of the Synergy Loan Agreement, and (2) guaranteed Synergy's obligation to pay Kingsland (which amount, if paid by United, will increase United's secured loan to Synergy by such amount) if the market price of AVH common stock on the fifth anniversary is less than $12 per ADR on the NYSE, for an aggregate maximum possible combined put payment and guarantee amount on the fifth anniversary of $217.2 million. United also agreed with Kingsland to share in any increase in value of AVH common stock within certain price ranges (the "Upside Sharing Agreement"). AVH Derivative Assets - The AVH Call Options, AVH Share Appreciation Rights and the Upside Sharing Agreement (collectively, the "AVH Derivative Assets") are recorded at fair value as Other assets on the Company's balance sheet and are included in the table above. Changes in the fair value of the AVH Derivative Assets are recorded as part of Nonoperating income (expense): Miscellaneous, net on the Company's statements of consolidated operations. Investments presented in the table above have the same fair value as their carrying value. The table below presents the carrying values and estimated fair values of financial instruments not presented in the tables above as of December 31 (in millions). Carrying amounts include any related discounts, premiums, issuance costs and origination costs:
Fair value of the financial instruments included in the tables above was determined as follows:
Investments in Regional Carriers. United holds investments in several regional carriers that fly for the Company as United Express under CPAs. The combined carrying value of the investments was approximately $144 million as of the date of this report. United accounts for each investment using the equity method. Each investment and United's ownership stake is listed below.
Other Investments. United owns approximately 9% of the preferred shares of Fulcrum BioEnergy, Inc. ("Fulcrum"), a company that is developing a process for transforming municipal solid waste into transportation fuels, including jet fuel and diesel. United records its investment in Fulcrum at cost less impairment, adjusted for observable price changes in orderly transactions for an identical or similar investment of the same issuer. As of December 31, 2018, the carrying value of United's investment was $48 million. |
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- References No definition available.
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- Definition The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Debt |
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| Debt Disclosure [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Debt | DEBT
(a) UAL is the issuer of this debt. United is a guarantor. The table below presents the Company's contractual principal payments (not including debt discount or debt issuance costs) at December 31, 2018 under then-outstanding long-term debt agreements in each of the next five calendar years (in millions):
Secured debt Credit and Guaranty Agreement. On March 29, 2017, United and UAL, as borrower and guarantor, respectively, entered into an Amended and Restated Credit and Guaranty Agreement (as amended, the "Credit Agreement"). The Credit Agreement consists of a $1.5 billion term loan due April 1, 2024 and a $2.0 billion revolving credit facility available for drawing until April 1, 2022. The obligations of United under the amended Credit Agreement are secured by liens on certain international route authorities, certain take-off and landing rights and related assets of United. Term loan borrowings under the Credit Agreement bear interest at a variable rate equal to LIBOR plus a margin of 1.75% per annum, or another rate based on certain market interest rates, plus a margin of 0.75% per annum. The principal amount of the term loan must be repaid in consecutive quarterly installments of 0.25% of the original principal amount thereof, commencing on June 30, 2017, with any unpaid balance due on April 1, 2024. United may prepay all or a portion of the loan from time to time, at par plus accrued and unpaid interest. As of December 31, 2018, United had its entire capacity of $2.0 billion available under the revolving credit facility of the Company's Credit Agreement. United pays a commitment fee equal to 0.75% per annum on the undrawn amount available under the revolving credit facility. If drawn, revolving loans under the Credit Agreement bear interest at a variable rate equal to LIBOR plus a margin of 2.25% per annum, or another rate based on certain market interest rates, plus a margin of 1.25% per annum. As of December 31, 2018, United had cash collateralized $73 million of letters of credit, which generally have evergreen clauses and are expected to be renewed on an annual basis. As of December 31, 2018, United also had $418 million of surety bonds securing various obligations with expiration dates through 2022. EETCs. As of December 31, 2018, United had $8.8 billion principal amount of equipment notes outstanding issued under EETC financings included in notes payable in the table of outstanding debt above. Generally, the structure of these EETC financings consists of pass-through trusts created by United to issue pass-through certificates, which represent fractional undivided interests in the respective pass-through trusts and are not obligations of United. The proceeds of the issuance of the pass-through certificates are used to purchase equipment notes which are issued by United and secured by its aircraft. The payment obligations under the equipment notes are those of United. Proceeds received from the sale of pass-through certificates are initially held by a depositary in escrow for the benefit of the certificate holders until United issues equipment notes to the trust, which purchases such notes with a portion of the escrowed funds. These escrowed funds are not guaranteed by United and are not reported as debt on United's consolidated balance sheet because the proceeds held by the depositary are not United's assets. In February 2018, May 2018 and February 2019, United created separate EETC pass-through trusts, each of which issued pass-through certificates. The proceeds of the issuance of the pass-through certificates are used to purchase equipment notes issued by United and secured by its aircraft. The Company records the debt obligation upon issuance of the equipment notes rather than upon the initial issuance of the pass-through certificates. Certain details of the pass-through trusts with proceeds received from issuance of debt in 2018 are as follows (in millions, except stated interest rate):
In 2018, United borrowed approximately $424 million aggregate principal amount from various financial institutions to finance the purchase of several aircraft delivered in 2018. The notes evidencing these borrowings, which are secured by the related aircraft, mature in 2030 and have interest rates comprised of LIBOR plus a specified margin. Unsecured debt 4.25% Senior Notes due 2022. In September 2017, UAL issued $400 million aggregate principal amount of 4.25% Senior Notes due October 1, 2022 (the "4.25% Senior Notes due 2022"). These notes are fully and unconditionally guaranteed and recorded by United on its balance sheet as debt. The indenture for the 4.25% Senior Notes due 2022 requires UAL to offer to repurchase the notes for cash if certain changes of control of UAL occur at a purchase price equal to 101% of the principal amount of notes repurchased plus accrued and unpaid interest. 5% Senior Notes due 2024. In January 2017, UAL issued $300 million aggregate principal amount of 5% Senior Notes due February 1, 2024 (the "5% Senior Notes due 2024"). These notes are fully and unconditionally guaranteed and recorded by United on its balance sheet as debt. The indenture for the 5% Senior Notes due 2024 requires UAL to offer to repurchase the notes for cash if certain changes of control of UAL occur at a purchase price equal to 101% of the principal amount of notes repurchased plus accrued and unpaid interest. As of December 31, 2018, UAL and United were in compliance with their respective debt covenants. The collateral, covenants and cross default provisions of the Company's principal debt instruments that contain such provisions are summarized in the table below:
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- References No definition available.
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- Definition The entire disclosure for long-term debt. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Leases and Capacity Purchase Agreements |
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| Leases and Capacity Purchase Agreements | LEASES AND CAPACITY PURCHASE AGREEMENTS United leases aircraft, airport passenger terminal space, aircraft hangars and related maintenance facilities, cargo terminals, other airport facilities, other commercial real estate, office and computer equipment and vehicles. In 2018, United entered into a new Airline Use and Lease Agreement at Chicago O'Hare International Airport ("Chicago O'Hare") with the City of Chicago with a lease term of approximately 15 years, effective May 12, 2018 through December 31, 2033. United also entered into several new ground and facility leases at Chicago O'Hare, effective May 12, 2018, for hangars, a ground equipment maintenance building, and employee parking with lease terms ranging from 15 years to 30 years. At December 31, 2018, United's scheduled future minimum lease payments under operating leases having initial or remaining noncancelable lease terms of more than one year, aircraft leases, including aircraft rent under CPAs and capital leases (substantially all of which are for aircraft) were as follows (in millions):
(a) Includes fair value lease and deferred financing fee balances, which are being amortized over the terms of their respective leases. (b) Includes airport construction projects managed by United in which United has construction risk, including project cost overruns. The Company recorded an asset for project costs and a related liability equal to project costs funded by parties other than United. As of December 31, 2018, United had an asset balance of $886 million recorded in operating property and equipment and $920 million recorded in current and long-term obligations under capital leases for these airport construction projects. As of December 31, 2018, United's aircraft capital lease minimum payments relate to leases of 28 mainline and 90 regional aircraft as well as to leases of nonaircraft assets. Imputed interest rate ranges are 3.5% to 115.1%. Aircraft operating leases have initial terms of five to 26 years, with expiration dates ranging from 2019 through 2029. Under the terms of most leases, United has the right to purchase the aircraft at the end of the lease term, in some cases, at fair market value, and in others, at fair market value or a percentage of cost. United is the lessee of real property under long-term operating leases at a number of airports where we are also the guarantor of approximately $1.3 billion of underlying debt and interest thereon as of December 31, 2018. These leases are typically with municipalities or other governmental entities, which are excluded from the consolidation requirements concerning a variable interest entity ("VIE"). To the extent United's leases and related guarantees are with a separate legal entity other than a governmental entity, United is not the primary beneficiary because the lease terms are consistent with market terms at the inception of the lease and the lease does not include a residual value guarantee, fixed-price purchase option, or similar feature. United has facility operating leases that extend to 2055. United's nonaircraft rent expense was approximately $1.3 billion, $1.3 billion and $1.2 billion for the years ended December 31, 2018, 2017 and 2016, respectively. In addition to nonaircraft rent and aircraft rent, which is separately presented in the consolidated statements of operations, United had aircraft rent related to regional aircraft operating leases, which is included as part of Regional capacity purchase expense in United's consolidated statement of operations, of $505 million, $458 million and $439 million for the years ended December 31, 2018, 2017 and 2016, respectively. In connection with UAL Corporation's and United Air Lines, Inc.'s (predecessors to UAL and United) fresh-start reporting requirements upon their exit from Chapter 11 bankruptcy protection in 2006 and the Company's acquisition accounting adjustments related to the Company's merger transaction in 2010, lease valuation adjustments for operating leases were initially recorded in the consolidated balance sheet, representing the net present value of the differences between contractual lease rates and the fair market lease rates for similar leased assets at the time. An asset (liability) results when the contractual lease rates are more (less) favorable than market lease terms at the valuation date. The lease valuation adjustment is amortized on a straight-line basis as an increase (decrease) to rent expense over the individual applicable remaining lease terms, resulting in recognition of rent expense as if United had entered into the leases at market rates. The related remaining lease terms, primarily related to aircraft which make up the majority of the fair value lease adjustment balance, are one to six years for United. The lease valuation adjustments are classified within other noncurrent liabilities and the net accretion amounts are $60 million, $79 million and $82 million for the years ended December 31, 2018, 2017 and 2016, respectively. Regional CPAs United has contractual relationships with various regional carriers to provide regional aircraft service branded as United Express. Under these CPAs, the Company pays the regional carriers contractually agreed fees (carrier costs) for operating these flights plus a variable reimbursement (incentive payment for operational performance) based on agreed performance metrics, subject to annual adjustments. The fees for carrier costs are based on specific rates for various operating expenses of the regional carriers, such as crew expenses, maintenance and aircraft ownership, some of which are multiplied by specific operating statistics (e.g., block hours, departures), while others are fixed monthly amounts. Under these CPAs, the Company is responsible for all fuel costs incurred, as well as landing fees and other costs, which are either passed through by the regional carrier to the Company without any markup or directly incurred by the Company, and, in some cases, the Company owns or leases some or all of the aircraft subject to the CPA, and leases or subleases, as applicable, such aircraft to the regional carrier. United's CPAs are for 559 regional aircraft as of December 31, 2018, and the CPAs have terms expiring through 2029. Aircraft operated under CPAs include aircraft leased directly from the regional carriers and those owned by United or leased from third-party lessors and operated by the regional carriers. See Part I, Item 2, Properties, of this report for additional information. In 2017, United entered into a five-year CPA with Air Wisconsin Airlines for regional service under the United Express brand to operate up to 65 CRJ200 aircraft. In addition, United extended the term of its existing CPA with ExpressJet Airlines to operate up to approximately 125 aircraft through December 31, 2022. United recorded approximately $979 million, $907 million and $935 million in expenses related to its CPAs with its regional carriers, in which United is a minority shareholder, for the years ended December 31, 2018, 2017 and 2016, respectively. There were approximately $53 million and $24 million in accounts payable due to these companies as of December 31, 2018 and December 31, 2017, respectively. There were no material accounts receivables due from these companies as of December 31, 2018 and December 31, 2017. The CPAs with these related parties were executed in the ordinary course of business. Our future commitments under our CPAs are dependent on numerous variables, and are, therefore, difficult to predict. The most important of these variables is the number of scheduled block hours. Although we are not required to purchase a minimum number of block hours under certain of our CPAs, we have set forth below estimates of our future payments under the CPAs based on our assumptions. United's estimates of its future payments under all of the CPAs do not include the portion of the underlying obligation for any aircraft leased to a regional carrier or deemed to be leased from other regional carriers and facility rent that are disclosed as part of aircraft and nonaircraft operating leases. For purposes of calculating these estimates, we have assumed (1) the number of block hours flown is based on our anticipated level of flight activity or at any contractual minimum utilization levels if applicable, whichever is higher, (2) that we will reduce the fleet as rapidly as contractually allowed under each CPA, (3) that aircraft utilization, stage length and load factors will remain constant, (4) that each carrier's operational performance will remain at historic levels and (5) an annual projected inflation rate. These amounts exclude variable pass-through costs such as fuel and landing fees, among others. Based on these assumptions as of December 31, 2018, our future payments through the end of the terms of our CPAs are presented in the table below (in billions):
The actual amounts we pay to our regional operators under CPAs could differ materially from these estimates. For example, a 10% increase or decrease in scheduled block hours for all of United's regional operators (whether as a result of changes in average daily utilization or otherwise) in 2019 would result in a corresponding change in annual cash obligations under the CPAs of approximately $160 million. |
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- References No definition available.
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- Definition The entire disclosure for lessee entity's leasing arrangements including, but not limited to, all of the following: (a.) The basis on which contingent rental payments are determined, (b.) The existence and terms of renewal or purchase options and escalation clauses, (c.) Restrictions imposed by lease agreements, such as those concerning dividends, additional debt, and further leasing. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Variable Interest Entities |
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| Organization, Consolidation and Presentation of Financial Statements [Abstract] | |||||||||
| Variable Interest Entities | VARIABLE INTEREST ENTITIES Variable interests are contractual, ownership or other monetary interests in an entity that change with fluctuations in the fair value of the entity's net assets exclusive of variable interests. A VIE can arise from items such as lease agreements, loan arrangements, guarantees or service contracts. An entity is a VIE if (a) the entity lacks sufficient equity or (b) the entity's equity holders lack power or the obligation and right as equity holders to absorb the entity's expected losses or to receive its expected residual returns. If an entity is determined to be a VIE, the entity must be consolidated by the primary beneficiary. The primary beneficiary is the holder of the variable interests that has the power to direct the activities of a VIE that (i) most significantly impact the VIE's economic performance and (ii) has the obligation to absorb losses of or the right to receive benefits from the VIE that could potentially be significant to the VIE. Therefore, the Company must identify which activities most significantly impact the VIE's economic performance and determine whether it, or another party, has the power to direct those activities. Aircraft Leases. We are the lessee in a number of operating leases covering the majority of our leased aircraft. The lessors are trusts established specifically to purchase, finance and lease aircraft to us. These leasing entities meet the criteria for VIEs. We are generally not the primary beneficiary of the leasing entities if the lease terms are consistent with market terms at the inception of the lease and do not include a residual value guarantee, fixed-price purchase option or similar feature that obligates us to absorb decreases in value or entitles us to participate in increases in the value of the aircraft. This is the case for many of our operating leases; however, leases of 23 mainline jet aircraft contain a fixed-price purchase option that allow United to purchase the aircraft at predetermined prices on specified dates during the lease term. Additionally, leases covering 90 leased regional jet aircraft contain an option to purchase the aircraft at the end of the lease term at prices that, depending on market conditions, could be below fair value. United has not consolidated the related trusts because, even taking into consideration these purchase options, United is still not the primary beneficiary. United's maximum exposure under these leases is the remaining lease payments, which are reflected in future lease commitments in Note 11 of this report. EETCs. United evaluated whether the pass-through trusts formed for its EETC financings, treated as either debt or aircraft operating leases, are VIEs required to be consolidated by United under applicable accounting guidance, and determined that the pass-through trusts are VIEs. Based on United's analysis as described below, United determined that it does not have a variable interest in the pass-through trusts. The primary risk of the pass-through trusts is credit risk (i.e. the risk that United, the issuer of the equipment notes, may be unable to make its principal and interest payments). The primary purpose of the pass-through trust structure is to enhance the credit worthiness of United's debt obligation through certain bankruptcy protection provisions, a liquidity facility (in certain of the EETC structures) and improved loan-to-value ratios for more senior debt classes. These credit enhancements lower United's total borrowing cost. Pass-through trusts are established to receive principal and interest payments on the equipment notes purchased by the pass-through trusts from United and remit these proceeds to the pass-through trusts' certificate holders. United does not invest in or obtain a financial interest in the pass-through trusts. Rather, United has an obligation to make interest and principal payments on its equipment notes held by the pass-through trusts. United did not intend to have any voting or non-voting equity interest in the pass-through trusts or to absorb variability from the pass-through trusts. Based on this analysis, the Company determined that it is not required to consolidate the pass-through trusts. Synergy affiliates.
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| X | ||||||||||
- References No definition available.
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- Definition The entire disclosure for a variable interest entity (VIE), including but not limited to, judgments and assumptions in determining whether to consolidate and in identifying the primary beneficiary, gain (loss) recognized on the initial consolidation of the VIE, terms of arrangements, amounts and classification of the VIE's assets and liabilities, and the entity's maximum exposure to loss. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Commitments and Contingencies |
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| Commitments and Contingencies Disclosure [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| COMMITMENTS AND CONTINGENCIES | NOTE 13 - COMMITMENTS AND CONTINGENCIES Commitments. As of December 31, 2018, United had firm commitments and options to purchase aircraft from The Boeing Company ("Boeing"), Airbus S.A.S. ("Airbus") and Embraer S.A. ("Embraer") presented in the table below:
The aircraft listed in the table above are scheduled for delivery from 2019 through 2027. To the extent the Company and the aircraft manufacturers with whom the Company has existing orders for new aircraft agree to modify the contracts governing those orders, the amount and timing of the Company's future capital commitments could change. In 2019, United expects to take delivery of 25 Embraer E175 aircraft, 20 Boeing 737 MAX aircraft, 8 Boeing 787 aircraft and 2 Boeing 777-300ER aircraft. United also has agreements to purchase 20 used Airbus A319 aircraft with expected delivery dates through 2022. During the third quarter of 2018, United entered into an agreement with the lessor of 54 Embraer ERJ 145 aircraft to purchase those aircraft in 2019. The provisions of such agreement resulted in a change in accounting classification of the applicable leases from operating leases to capital leases up until the applicable purchase date. The table below summarizes United's commitments as of December 31, 2018, which primarily relate to the acquisition of aircraft and related spare engines, aircraft improvements and include other capital purchase commitments for the years ended December 31 (in billions). Any new firm aircraft orders, including through the exercise of purchase options and purchase rights, will increase the total future capital commitments of the Company.
In February 2019, the Company secured $1.0 billion of EETC financing to finance certain aircraft deliveries in 2018 and 2019. The Company has also secured backstop financing commitments from certain of its aircraft manufacturers for a limited number of its future aircraft deliveries, subject to certain customary conditions. Financing may be necessary to satisfy the Company's capital commitments for its firm order aircraft and other related capital expenditures. Legal and Environmental. The Company has certain contingencies resulting from litigation and claims incident to the ordinary course of business. As of December 31, 2018, management believes, after considering a number of factors, including (but not limited to) the information currently available, the views of legal counsel, the nature of contingencies to which the Company is subject and prior experience, that the ultimate disposition of the litigation and claims will not materially affect the Company's consolidated financial position or results of operations. The Company records liabilities for legal and environmental claims when a loss is probable and reasonably estimable. These amounts are recorded based on the Company's assessments of the likelihood of their eventual disposition. Guarantees and Indemnifications. In the normal course of business, the Company enters into numerous real estate leasing and aircraft financing arrangements that have various guarantees included in the contracts. These guarantees are primarily in the form of indemnities under which the Company typically indemnifies the lessors and any tax/financing parties against tort liabilities that arise out of the use, occupancy, operation or maintenance of the leased premises or financed aircraft. Currently, the Company believes that any future payments required under these guarantees or indemnities would be immaterial, as most tort liabilities and related indemnities are covered by insurance (subject to deductibles). Additionally, certain leased premises such as fueling stations or storage facilities include indemnities of such parties for any environmental liability that may arise out of or relate to the use of the leased premises. As of December 31, 2018, United is the guarantor of approximately $1.9 billion in aggregate principal amount of tax-exempt special facilities revenue bonds and interest thereon. These bonds, issued by various airport municipalities, are payable solely from rentals paid under long-term agreements with the respective governing bodies. The leasing arrangements associated with approximately $1.3 billion of these obligations are accounted for as operating leases with the associated expense recorded on a straight-line basis resulting in ratable accrual of the lease obligation over the expected lease term. These tax-exempt special facilities revenue bonds are included in our lease commitments disclosed in Note 11 of this report. The leasing arrangements associated with approximately $466 million of these obligations are accounted for as capital leases. All of these bonds are due between 2019 and 2038. In connection with funding the Synergy Loan Agreement, the Company entered into an agreement with AVH's significant minority shareholder, Kingsland Holdings Limited ("Kingsland"), pursuant to which, in return for Kingsland's pledge of its 144.8 million shares of AVH common stock (equivalent to 18.1 million American Depositary Receipts ("ADRs")) and its consent to Synergy's pledge of its AVH common stock to United under the Synergy Loan Agreement, United (1) granted to Kingsland the right to put its shares of AVH common stock to United at market price on the fifth anniversary of the Synergy Loan Agreement, and (2) guaranteed Synergy's obligation to pay Kingsland (which amount, if paid by United, will increase United's secured loan to Synergy by such amount) if the market price of AVH common stock on the fifth anniversary is less than $12 per ADR on the NYSE, for an aggregate maximum possible combined put payment and guarantee amount on the fifth anniversary of $217.2 million. Accordingly, the Company recorded a liability of $31 million for the fair value of its guarantee to loan additional funds to Synergy if required. Any additional loans to Synergy would be collateralized by Synergy's shares of AVH stock and other collateral. Increased Cost Provisions. In United's financing transactions that include loans, United typically agrees to reimburse lenders for any reduced returns with respect to the loans due to any change in capital requirements and, in the case of loans in which the interest rate is based on LIBOR, for certain other increased costs that the lenders incur in carrying these loans as a result of any change in law, subject, in most cases, to obligations of the lenders to take certain limited steps to mitigate the requirement for, or the amount of, such increased costs. At December 31, 2018, the Company had $3.5 billion of floating rate debt and $27 million of fixed rate debt, with remaining terms of up to 12 years, that are subject to these increased cost provisions. In several financing transactions involving loans or leases from non-U.S. entities, with remaining terms of up to 12 years and an aggregate balance of $3.2 billion, the Company bears the risk of any change in tax laws that would subject loan or lease payments thereunder to non-U.S. entities to withholding taxes, subject to customary exclusions. As of December 31, 2018, United is the guarantor of $145 million of aircraft mortgage debt issued by one of United's regional carriers. The aircraft mortgage debt is subject to similar increased cost provisions as described above for the Company's debt, and the Company would potentially be responsible for those costs under the guarantees. Fuel Consortia. United participates in numerous fuel consortia with other air carriers at major airports to reduce the costs of fuel distribution and storage. Interline agreements govern the rights and responsibilities of the consortia members and provide for the allocation of the overall costs to operate the consortia based on usage. The consortia (and in limited cases, the participating carriers) have entered into long-term agreements to lease certain airport fuel storage and distribution facilities that are typically financed through tax-exempt bonds, either special facilities lease revenue bonds or general airport revenue bonds, issued by various local municipalities. In general, each consortium lease agreement requires the consortium to make lease payments in amounts sufficient to pay the maturing principal and interest payments on the bonds. As of December 31, 2018, approximately $1.7 billion principal amount of such bonds were secured by significant fuel facility leases in which United participates, as to which United and each of the signatory airlines has provided indirect guarantees of the debt. As of December 31, 2018, the Company's contingent exposure was approximately $164 million principal amount of such bonds based on its recent consortia participation. The Company's contingent exposure could increase if the participation of other air carriers decreases. The guarantees will expire when the tax-exempt bonds are paid in full, which ranges from 2022 to 2051. The Company did not record a liability at the time these indirect guarantees were made. Regional Capacity Purchase. As of December 31, 2018, United had 292 call options to purchase regional jet aircraft being operated by certain of its regional carriers with contract dates extending until 2029. These call options are exercisable upon wrongful termination or breach of contract, among other conditions. None of the call options were exercisable at December 31, 2018. Credit Card Processing Agreements. The Company has agreements with financial institutions that process customer credit card transactions for the sale of air travel and other services. Under certain of the Company's credit card processing agreements, the financial institutions in certain circumstances have the right to require that the Company maintain a reserve equal to a portion of advance ticket sales that has been processed by that financial institution, but for which the Company has not yet provided the air transportation. Such financial institutions may require additional cash or other collateral reserves to be established or additional withholding of payments related to receivables collected if the Company does not maintain certain minimum levels of unrestricted cash, cash equivalents and short-term investments (collectively, "Unrestricted Liquidity"). The Company's current level of Unrestricted Liquidity is substantially in excess of these minimum levels. Labor Negotiations. As of December 31, 2018, United, including its subsidiaries, had approximately 92,000 employees. Approximately 83% of United's employees were represented by various U.S. labor organizations as of December 31, 2018. The agreement with the International Brotherhood of Teamsters (the "IBT") contains provisions that require the Company to align contract terms with other airlines' workgroups under certain conditions. On October 23, 2018, United's Catering Operations employees voted to unionize under the Railway Labor Act. In an election overseen by the National Mediation Board, UNITE HERE received the majority of the votes and was officially certified to represent United's frontline Catering Operations employees. The Company expects contract negotiations to begin in 2019. |
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- Definition The entire disclosure for commitments and contingencies. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Special Charges |
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| Business Combinations [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| SPECIAL CHARGES | SPECIAL CHARGES Special charges in the statements of consolidated operations consisted of the following for the years ended December 31 (in millions):
(a) Amounts adjusted due to the adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606) and Accounting Standards Update No. 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost. See Note 1 to the financial statements contained in Part II, Item 8 of this report for additional information. 2018 The Company conducted its annual impairment review of intangible assets in the fourth quarter of 2018, which consisted of a comparison of the book value of specific assets to the fair value of those assets. Due to increased costs without sufficient corresponding increases in revenue in the Hong Kong market, the Company determined that the value of its Hong Kong routes had been impaired. Accordingly, in the fourth quarter of 2018, the Company recorded a special non-cash impairment charge of $206 million ($160 million net of taxes) associated with its Hong Kong routes. The collateral pledged under the Company's term loan, including the Hong Kong routes, continues to be sufficient to satisfy the loan covenants. The Company determined the fair value of the Hong Kong routes using a variation of the income approach known as the excess earnings method, which discounts an asset's projected future net cash flows to determine the current fair value. Assumptions used in the discounted cash flow methodology include a discount rate, which is based upon the Company's current weighted average cost of capital plus an asset-specific risk factor, and a projection of sales, expenses, gross margin, tax rates and contributory asset charges for four future years and a terminal growth rate. The assumptions used for future projections are determined based upon the Company's asset-specific forecasts along with the Company's strategic plan. These assumptions are inherently uncertain as they relate to future events and circumstances. Actual results will be influenced by the competitive environment, fuel costs and other expenses, and potentially other unforeseen events or circumstances that could have a material negative impact on future results. In May 2018, the Brazil–United States open skies agreement was ratified, which provides air carriers with unrestricted access between the United States and Brazil. The Company determined that the approval of the open skies agreement impaired the entire value of its Brazil route authorities because the agreement removes all limitations or reciprocity requirements for flights between the United States and Brazil. Accordingly, the Company recorded a $105 million special charge ($82 million net of taxes) to write off the entire value of the intangible asset associated with its Brazil routes. This asset is not part of any collateral pledged against any of the Company's borrowings. The Company continues to maintain its slot assets related to Brazil since airport access is still regulated by slot allocations that are limited by airport facility constraints. During 2018, the Company also recorded $66 million ($51 million net of taxes) of fair value adjustments related to aircraft purchased off lease, write-offs of unexercised aircraft purchase options and other impairments related to certain fleet types and international slots no longer in use. During 2018, the Company recorded a one-time termination charge of $64 million ($50 million net of tax) related to one of its engine maintenance service agreements. During 2018, the Company recorded severance and benefit costs related to a voluntary early-out program for its technicians and related employees represented by the IBT of $22 million ($17 million net of taxes). In the first quarter of 2017, approximately 1,000 technicians and related employees elected to voluntarily separate from the Company and receive a severance payment, with a maximum value of $100,000 per participant, based on years of service, with retirement dates through the end of 2018. Also during 2018, the Company recorded other management severance of $19 million ($15 million net of taxes). During 2018, the Company recorded gains of $28 million ($22 million net of taxes) for the change in market value of certain of its equity investments. Also, the Company recorded losses of $33 million ($26 million net of taxes) for the change in fair value of certain derivative assets related to equity of Avianca Holdings S.A. For equity investments and derivative assets subject to MTM accounting, the Company records gains and losses as part of Nonoperating income (expense): Miscellaneous, net in its statements of consolidated operations. 2017 During 2017 the Company recorded a $10 million ($6 million net of taxes) impairment charge related to obsolete spare parts inventory and a $15 million ($10 million net of taxes) intangible asset impairment charge related to a maintenance service agreement. During 2017, the Company recorded $83 million ($53 million net of taxes) of severance and benefit costs related to the voluntary early-out program for its technicians and related employees represented by the IBT as described above. Also during 2017, the Company recorded $33 million ($21 million net of taxes) of other management severance. 2016 In April 2016, the Federal Aviation Administration ("FAA") announced that it will designate Newark Liberty International Airport ("Newark") as a Level 2 schedule-facilitated airport under the International Air Transport Association Worldwide Slot Guidelines. The designation was associated with an updated demand and capacity analysis of Newark by the FAA. In 2016, the Company determined that the FAA's action impaired the entire value of its Newark slots because the slots are no longer the mechanism that governs take-off and landing rights. Accordingly, the Company recorded a $412 million special charge ($264 million net of taxes) to write off the intangible asset. During 2016, the Company recorded $37 million ($24 million net of taxes) of severance and benefit costs related to a voluntary early-out program for the Company's flight attendants and other severance agreements. In 2014, more than 2,500 flight attendants elected to voluntarily separate from the Company for a severance payment, with a maximum value of $100,000 per participant, based on years of service, with retirement dates through the end of 2016. In 2016, the City of Cleveland agreed to amend the Company's lease, which runs through 2029, associated with certain excess airport terminal space (principally Terminal D) and related facilities at Hopkins International Airport ("Cleveland"). The Company recorded an accrual for remaining payments under the lease for facilities that the Company no longer uses and will continue to incur costs under the lease without economic benefit to the Company. This liability was measured and recorded at its fair value when the Company ceased its right to use such facilities leased to it pursuant to the lease. The Company recorded a net charge of $74 million ($47 million net of taxes) related to the amended lease. The fleet service, passenger service, storekeeper and other employees represented by the International Association of Machinists and Aerospace Workers (the "IAM") ratified seven new contracts with the Company which extended the contracts through 2021. The technicians and related employees represented by the IBT ratified a six-year joint collective bargaining agreement which extended the contract through 2022. During 2016, the Company recorded $171 million ($110 million net of taxes) of special charges primarily for payments in conjunction with the IAM and IBT agreements described above. As part of the ratified contract with the IBT, the Company amended some of its technicians and related employees' postretirement medical plans. The amendments triggered curtailment accounting, resulting in the recognition of a one-time $60 million gain ($38 million net of taxes) for accelerated recognition of a prior service credit in one of the plans. Also, as part of the ratified contract with the Association of Flight Attendants, the Company amended two of its flight attendant postretirement medical plans. The amendments triggered curtailment accounting, resulting in the recognition of a one-time $47 million gain ($30 million net of taxes) for accelerated recognition of a prior service credit. Accrual Activity Activity related to the accruals for severance and medical costs and future lease payments on permanently grounded aircraft is as follows (in millions):
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- Definition The entire description for costs incurred to effect a business combination that have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| Quarterly Financial Information Disclosure [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Selected Quarterly Financial Data (Unaudited) | NOTE 15 - SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)
(a) Amounts adjusted due to the adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606) and Accounting Standards Update No. 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost. See Note 1 to the financial statements contained in Part II, Item 8 of this report for additional information. UAL's quarterly financial data is subject to seasonal fluctuations and historically its second and third quarter financial results, which reflect higher travel demand, are better than its first and fourth quarter financial results. UAL's quarterly results were impacted by the following significant items (in millions):
(a) Amounts adjusted due to the adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606). See Note 1 to the financial statements contained in Part II, Item 8 of this report for additional information. See Note 14 of this report for additional information related to these items. |
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- Definition The entire disclosure for quarterly financial data. Includes, but is not limited to, tabular presentation of financial information for fiscal quarters, effect of year-end adjustments, and an explanation of matters or transactions that affect comparability of the information. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Schedule II - Valuation and Qualifying Accounts |
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| Valuation and Qualifying Accounts [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Schedule II - Valuation and Qualifying Accounts | Schedule II Valuation and Qualifying Accounts For the Years Ended December 31, 2018, 2017 and 2016
(a) Deduction from reserve for purpose for which reserve was created. |
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- Definition The entire disclosure for any allowance and reserve accounts (their beginning and ending balances, as well as a reconciliation by type of activity during the period). Alternatively, disclosure of the required information may be within the footnotes to the financial statements or a supplemental schedule to the financial statements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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Significant Accounting Policies (Policies) |
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| Accounting Policies [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Use of Estimates | Use of Estimates—The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America ("GAAP") requires management to make estimates and assumptions that affect the amounts reported in these financial statements and accompanying notes. Actual results could differ from those estimates. |
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| Revenue Recognition | Revenue Recognition— The Company presents Passenger revenue, Cargo revenue and Other operating revenue on its income statement. Passenger revenue is recognized when transportation is provided and Cargo revenue is recognized when shipments arrive at their destination. Other operating revenue is recognized as the related performance obligations are satisfied. Passenger tickets and related ancillary services sold by the Company for mainline and regional flights are purchased primarily via credit card transactions, with payments collected by the Company in advance of the performance of related services. The Company initially records ticket sales in its Advance ticket sales liability, deferring revenue recognition until the travel occurs. For travel that has more than one flight segment, the Company deems each segment as a separate performance obligation and recognizes revenue for each segment as travel occurs. Tickets sold by other airlines where the Company provides the transportation are recognized as passenger revenue at the estimated value to be billed to the other airline when travel is provided. Differences between amounts billed and the actual amounts may be rejected and rebilled or written off if the amount recorded was different from the original estimate. When necessary, the Company records a reserve against its billings and payables with other airlines based on historical experience. The Company sells certain tickets with connecting flights with one or more segments operated by its other airline partners. For segments operated by its other airline partners, the Company has determined that it is acting as an agent on behalf of the other airlines as they are responsible for their portion of the contract (i.e. transportation of the passenger). The Company, as the agent, recognizes revenue within Other operating revenue at the time of the travel for the net amount representing commission to be retained by the Company for any segments flown by other airlines. Refundable tickets expire after one year from the date of issuance. Non-refundable tickets generally expire on the date of the intended travel, unless the date is extended by notification from the customer on or before the intended travel date. The Company records breakage revenue on the travel date for its estimate of tickets that will expire unused. To determine breakage, the Company uses its historical experience with refundable and nonrefundable expired tickets and other facts, such as recent aging trends, program changes and modifications that could affect the ultimate expiration patterns of tickets. Fees charged in association with changes or extensions to non-refundable tickets are considered part of the Company's passenger travel obligation. As such, those fees are deferred at the time of collection and recognized at the time the travel is provided. United initially capitalizes the costs of selling airline travel tickets and then recognizes those costs as Distribution expense at the time of travel. Passenger ticket costs include credit card fees, travel agency and other commissions paid, as well as global distribution systems booking fees. Advance Ticket Sales. Advance ticket sales represent the Company's liability to provide air transportation in the future. In the years ended December 31, 2018 and 2017, the Company recognized approximately $3.1 billion and $2.9 billion, respectively, of passenger revenue for tickets that were included in Advance ticket sales at the beginning of those periods. All tickets sold at any given point of time have travel dates extending up to twelve months. As a result, the balance of the Company's Advance ticket sales liability represents activity that will be recognized in the next twelve months.
The Company deploys its aircraft across its route network through a single route scheduling system to maximize its value. When making resource allocation decisions, the Company's chief operating decision maker evaluates flight profitability data, which considers aircraft type and route economics. The Company's chief operating decision maker makes resource allocation decisions to maximize the Company's consolidated financial results. Managing the Company as one segment allows management the opportunity to maximize the value of its route network. The Company attributes revenue among the geographic areas based upon the origin and destination of each flight segment. The Company's operations involve an insignificant level of dedicated revenue-producing assets in geographic regions as the overwhelming majority of the Company's revenue-producing assets (primarily U.S. registered aircraft) can be deployed in any of its geographic regions. Ancillary Fees. The Company charges fees, separately from ticket sales, for certain ancillary services that are directly related to passengers' travel, such as ticket change fees, baggage fees, inflight amenities fees, and other ticket-related fees. These ancillary fees are part of the travel performance obligation and, as such, are recognized as passenger revenue when the travel occurs. |
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| Frequent Flyer Accounting | Frequent Flyer Accounting— United's MileagePlus loyalty program builds customer loyalty by offering awards, benefits and services to program participants. Members in this program earn miles for travel on United, United Express, Star Alliance members and certain other airlines that participate in the program. Members can also earn miles by purchasing the goods and services of our network of non-airline partners. We have contracts to sell miles to these partners with the terms extending from one to eight years. These partners include domestic and international credit card issuers, retail merchants, hotels, car rental companies and our participating airline partners. Miles can be redeemed for free (other than taxes and government imposed fees), discounted or upgraded air travel and non-travel awards. Miles expire after 18 months of member account inactivity. Miles Earned in Conjunction with Travel. When frequent flyers earn miles for flights, the Company recognizes a portion of the ticket sales as revenue when the travel occurs and defers a portion of the ticket sale representing the value of the related miles as a separate performance obligation. The Company determines the estimated selling price of travel and miles as if each element is sold on a separate basis. The total consideration from each ticket sale is then allocated to each of these elements, individually, on a pro-rata basis. At the time of travel, the Company records the portion allocated to the miles to Frequent flyer deferred revenue on the Company's consolidated balance sheet and subsequently recognizes it into revenue when miles are redeemed for air travel and non-air travel awards. The Company's estimated selling price of miles is based on an equivalent ticket value less breakage, which incorporates the expected redemption of miles, as the best estimate of selling price for these miles. The equivalent ticket value is based on the prior 12 months' weighted average equivalent ticket value of similar fares as those used to settle award redemptions while taking into consideration such factors as redemption pattern, cabin class, loyalty status and geographic region. The estimated selling price of miles is adjusted by breakage that considers a number of factors, including redemption patterns of various customer groups. The Company reviews its breakage estimates annually based upon the latest available information regarding redemption and expiration patterns. The Company's estimate of the expected expiration of miles requires significant management judgment. Current and future changes to expiration assumptions or to the expiration policy, or to program rules and program redemption opportunities, may result in material changes to the deferred revenue balance as well as recognized revenues from the program. For the portion of the outstanding miles that we estimate will not be redeemed, we recognize the associated value proportionally as the remaining miles are redeemed. Co-Brand Agreement. United has a significant contract (the "Co-Brand Agreement") to sell MileagePlus miles to its co-branded credit card partner Chase Bank USA, N.A. ("Chase"). Chase awards miles to MileagePlus members based on their credit card activity. United identified the following significant separately identifiable performance obligations in the Co-Brand Agreement:
We account for all the payments received (including monthly and one-time payments) under the Co-Brand Agreement by allocating them to the separately identifiable performance obligations. The fair value of the separately identifiable performance obligations is determined using management's estimated selling price of each component. The objective of using the estimated selling price based methodology is to determine the price at which we would transact a sale if the product or service were sold on a stand-alone basis. Accordingly, we determine our best estimate of selling price by considering multiple inputs and methods including, but not limited to, discounted cash flows, brand value, volume discounts, published selling prices, number of miles awarded and number of miles redeemed. The Company estimated the selling prices and volumes over the term of the Co-Brand Agreement in order to determine the allocation of proceeds to each of the components to be delivered. We also evaluate volumes on an annual basis, which may result in a change in the allocation of the estimated consideration from the Co-Brand Agreement on a prospective basis. Frequent flyer deferred revenue. Miles in MileagePlus members' accounts are combined into one homogeneous pool and are thus not separately identifiable, for award redemption purposes, between miles earned in the current period and those in their beginning balance. Of the miles expected to be redeemed, the Company expects the majority of these miles to be redeemed within two years. |
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| Cash and Cash Equivalents and Restricted Cash | Cash and Cash Equivalents and Restricted Cash— Highly liquid investments with a maturity of three months or less on their acquisition date are classified as cash and cash equivalents. Restricted cash primarily includes cash collateral for letters of credit and collateral associated with obligations for facility leases and other insurance-related obligations. Restricted cash is classified as short-term or long-term in the consolidated balance sheets based on the expected timing of return of the assets to the Company. |
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| Short-term Investments | Short-term Investments—Debt investments are classified as available-for-sale and are stated at fair value. Realized gains and losses on sales of these investments are reflected in Miscellaneous, net in the consolidated statements of operations. Unrealized gains and losses on available-for-sale securities are reflected as a component of accumulated other comprehensive income (loss). Equity investments with readily determinable fair values are measured at fair value. Equity investments without readily determinable fair values are measured using the equity method, or measured at cost with adjustments for observable changes in price or impairments (referred to as the measurement alternative). Changes in fair value are recorded in Miscellaneous, net in the consolidated statements of operations. |
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| Accounts Receivable | Accounts Receivable. Accounts receivable primarily consist of amounts due from credit card companies, non-airline partners, and cargo transportation customers. We provide an allowance for uncollectible accounts equal to the estimated losses expected to be incurred based on historical write-offs and other specific analyses. |
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| Aircraft Fuel, Spare Parts and Supplies | Aircraft Fuel, Spare Parts and Supplies—The Company accounts for aircraft fuel, spare parts and supplies at average cost and provides an obsolescence allowance for aircraft spare parts with an assumed residual value of 10% of original cost. |
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| Property and Equipment | Property and Equipment—The Company records additions to owned operating property and equipment at cost when acquired. Property under capital leases and the related obligation for future lease payments are recorded at an amount equal to the initial present value of those lease payments. Modifications that enhance the operating performance or extend the useful lives of airframes or engines are capitalized as property and equipment. It is the Company's policy to record compensation from delays in delivery of aircraft as a reduction of the cost of the related aircraft. Depreciation and amortization of owned depreciable assets is based on the straight-line method over the assets' estimated useful lives. Leasehold improvements are amortized over the remaining term of the lease, including estimated facility renewal options when renewal is reasonably assured at key airports, or the estimated useful life of the related asset, whichever is less. Properties under capital leases are amortized on the straight-line method over the life of the lease or, in the case of certain aircraft, over their estimated useful lives, whichever is shorter. Amortization of capital lease assets is included in depreciation and amortization expense. |
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| Maintenance and Repairs | Maintenance and Repairs—The cost of maintenance and repairs, including the cost of minor replacements, is charged to expense as incurred, except for costs incurred under our power-by-the-hour ("PBTH") engine maintenance agreements. PBTH contracts transfer certain risk to third-party service providers and fix the amount we pay per flight hour or per cycle to the service provider in exchange for maintenance and repairs under a predefined maintenance program. Under PBTH agreements, the Company recognizes expense at a level rate per engine hour, unless the level of service effort and the related payments during the period are substantially consistent, in which case the Company recognizes expense based on the amounts paid. |
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| Lease Fair Value Adjustments | Lease Fair Value Adjustments—Lease fair value adjustments, which arose from recording operating leases at fair value under fresh start or business combination accounting, are amortized on a straight-line basis over the related lease term. |
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| Regional Capacity Purchase | Regional Capacity Purchase—Payments made to regional carriers under capacity purchase agreements ("CPAs") are reported in Regional capacity purchase in our consolidated statements of operations. |
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| Advertising | Advertising—Advertising costs, which are included in Other operating expenses, are expensed as incurred. |
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| Intangibles | Intangibles—The Company has finite-lived and indefinite-lived intangible assets, including goodwill. Finite-lived intangible assets are amortized over their estimated useful lives. Goodwill and indefinite-lived intangible assets are not amortized but are reviewed for impairment annually or more frequently if events or circumstances indicate that the asset may be impaired. Goodwill and indefinite-lived assets are reviewed for impairment on an annual basis as of October 1, or on an interim basis whenever a triggering event occurs. See Note 2 of this report for additional information related to intangibles. |
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| Long-Lived Asset Impairments | Long-Lived Asset Impairments—The Company evaluates the carrying value of long-lived assets subject to amortization whenever events or changes in circumstances indicate that an impairment may exist. For purposes of this testing, the Company has generally identified the aircraft fleet type as the lowest level of identifiable cash flows. An impairment charge is recognized when the asset's carrying value exceeds its net undiscounted future cash flows and its fair market value. The amount of the charge is the difference between the asset's carrying value and fair market value. See Note 14 of this report for additional information related to asset impairments. |
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| Share-Based Compensation | Share-Based Compensation—The Company measures the cost of employee services received in exchange for an award of equity instruments based on the grant date fair value of the award. The resulting cost is recognized over the period during which an employee is required to provide service in exchange for the award, usually the vesting period. Obligations for cash-settled restricted stock units ("RSUs") are remeasured at fair value throughout the requisite service period at the close of the reporting period based upon UAL's stock price. In addition to the service requirement, certain RSUs have performance metrics that must be achieved prior to vesting. These awards are accrued based on the expected level of achievement at each reporting period. An adjustment is recorded each reporting period to adjust compensation expense based on both UAL's stock price and the then current level of expected performance achievement for the performance-based awards. |
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| Ticket Taxes | Ticket Taxes—Certain governmental taxes are imposed on the Company's ticket sales through a fee included in ticket prices. The Company collects these fees and remits them to the appropriate government agency. These fees are recorded on a net basis and, as a result, are excluded from revenue. |
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| Retirement of Leased Aircraft | Retirement of Leased Aircraft—The Company accrues for estimated lease costs over the remaining term of the lease at the present value of future minimum lease payments, net of estimated sublease rentals (if any), in the period that aircraft are permanently removed from service. When reasonably estimable and probable, the Company estimates maintenance lease return condition obligations for items such as minimum aircraft and engine conditions specified in leases and accrues these amounts over the lease term while the aircraft are operating, and any remaining unrecognized estimated obligations are accrued in the period that an aircraft is removed from service. |
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| Uncertain Income Tax Positions | Uncertain Income Tax Positions—The Company has recorded reserves for income taxes and associated interest that may become payable in future years. Although management believes that its positions taken on income tax matters are reasonable, the Company nevertheless has established tax and interest reserves in recognition that various taxing authorities may challenge certain of the positions taken by the Company, potentially resulting in additional liabilities for taxes and interest. The Company's uncertain tax position reserves are reviewed periodically and are adjusted as events occur that affect its estimates, such as the availability of new information, the lapsing of applicable statutes of limitation, the conclusion of tax audits, the measurement of additional estimated liability, the identification of new tax matters, the release of administrative tax guidance affecting its estimates of tax liabilities, or the rendering of relevant court decisions. The Company records penalties and interest relating to uncertain tax positions as part of income tax expense in its consolidated statements of operations. |
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| Labor Costs | Labor Costs—The Company records expenses associated with amendable labor agreements when the amounts are probable and estimable. These include costs associated with lump sum cash payments that would be made in conjunction with the ratification of labor agreements. To the extent these upfront costs are in lieu of future pay increases, they would be capitalized and amortized over the term of the labor agreements. If not, these amounts would be expensed. |
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| Third-Party Business | Third-Party Business—The Company has third-party business revenue that includes fuel sales, catering, ground handling, maintenance services and frequent flyer award non-air redemptions. Third-party business revenue is recorded in Other operating revenue. The Company also incurs third-party business expenses, such as maintenance, ground handling and catering services for third parties, fuel sales and non-air mileage redemptions. The third-party business expenses are recorded in Other operating expenses, except for non-air mileage redemption. Non-air mileage redemption expenses are recorded to Other operating revenue. |
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| Recently Issued Accounting Standards | Recently Issued Accounting Standards— The Company adopted Financial Accounting Standards Board ("FASB") Accounting Standards Codification Topic 606, Revenue from Contracts with Customers (the "New Revenue Standard"), effective January 1, 2018 using the full-retrospective method. Topic 606 prescribes that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. For the Company, the most significant impact of the standard was the reclassification of certain ancillary fees from other operating revenue into passenger revenue on the statement of consolidated operations. These ancillary fees are directly related to passenger travel, such as ticket change fees and baggage fees, and are no longer considered distinct performance obligations separate from the passenger travel component. In addition, the ticket change fees, which were previously recognized when received, are now recognized when transportation is provided. Adoption of the standard had no impact on the Company's consolidated cash flows statements. The Company adopted Accounting Standards Update No. 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost (the "New Retirement Standard"), effective January 1, 2018 using the full-retrospective method. The New Retirement Standard requires employers to present the service cost component of the net periodic benefit cost in the same income statement line item as other employee compensation costs arising from services rendered during the period. The other components of net benefit cost, including interest cost, expected return on plan assets, amortization of prior service cost/credit and actuarial gain/loss, and settlement and curtailment effects, are to be presented outside of any subtotal of operating income. The Company elected to apply the practical expedient and use the amounts disclosed in Note 8 to the financial statements included in Part II, Item 8 of the Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2017 as the estimation basis for applying the retrospective presentation requirements of the standard. The New Revenue Standard and the New Retirement Standard had the same impact on the financial statements of United as they had on the financial statements of UAL. The tables below present the impact of the adoption of the New Revenue Standard and the New Retirement Standard on select accounts and captions of UAL's statements of consolidated operations for the twelve months ended December 31, 2017 and 2016 (in millions, except per share amounts) and the impact on UAL's balance sheet accounts and captions as of December 31, 2017 (in millions):
The Company adopted Accounting Standards Update No. 2016-01, Financial Instruments—Overall (Subtopic 825-10) effective January 1, 2018. This standard made several changes, including the elimination of the available-for-sale classification of equity investments, and requires equity investments with readily determinable fair values to be measured at fair value with changes in fair value recognized in earnings. The Company reclassified to retained earnings $6 million of unrealized loss, net of tax, on the Company's investment in Azul, S.A. ("Azul") which was previously classified as an available-for-sale security. See Notes 6 and 9 to the financial statements included in this Part II, Item 8 for additional information. In June 2016, the FASB issued Accounting Standards Update No. 2016-13, Financial Instruments—Credit Losses ("ASU 2016-13"). The main objective is to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. The amendments in this update replace the incurred loss methodology with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to calculate credit loss estimates. For trade receivables, loans and held-to-maturity debt securities, entities will be required to estimate lifetime expected credit losses. For available-for-sale debt securities, entities will be required to recognize an allowance for credit losses rather than a reduction to the carrying value of the asset. The amendments are effective for public business entities for fiscal years and interim periods beginning after December 15, 2019. The Company is evaluating the impact the adoption of ASU 2016-13 will have on its consolidated financial statements and believes that it will not have a material impact on its consolidated financial statements. In 2016, the FASB amended the FASB Accounting Standards Codification and created a new Topic 842, Leases (the "New Lease Standard"). The guidance requires lessees to recognize a right-of-use asset and a lease liability for all leases (with the exception of short-term leases) at the commencement date and recognize expenses on their income statements similar to the current Topic 840, Leases ("Topic 840"). The New Lease Standard is effective for fiscal years and interim periods beginning after December 15, 2018. The Company adopted this standard on January 1, 2019 using a modified retrospective approach for all leases existing at or commencing after the date of initial application and utilizing certain practical expedients. The adoption of the New Lease Standard is expected to impact our reported results as shown in the tables below (in millions, except per share amounts):
(a) Finance leases, under the New Lease Standard, are the equivalent of capital leases under Topic 840. The adoption of the New Lease Standard primarily resulted in the recording of assets and obligations of our operating leases on our consolidated balance sheets. Certain amounts recorded for prepaid and accrued rent associated with historical operating leases were reclassified to the newly captioned Operating lease assets in the consolidated balance sheets. Also, certain leases designated under Topic 840 as owned assets and capitalized finance leases will not be considered assets under the New Lease Standard and will be removed from the consolidated balance sheets, along with the related capital lease liability.
The expense for leases under the New Lease Standard will continue to be classified in their historical income statement captions (primarily in Aircraft rent, Landing fees and other rent and Regional capacity purchase in our statements of consolidated operations). The adoption of the New Lease Standard also resulted in the recharacterization of certain leases from capital leases under Topic 840 to operating leases under the New Lease Standard. This change will result in less depreciation and amortization and interest expense associated with capital leases offset by higher lease expense associated with operating leases. The change is associated with leases of aircraft under certain CPAs and certain airport facilities. The reduction in capitalized interest is also associated with the same airport facilities. |
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- Definition Aircraft Fuel Spare Parts And Supplies No definition available.
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- Definition Labor Costs Policy No definition available.
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- Definition Lease Fair Value Adjustments No definition available.
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- Definition Regional Capacity Purchase No definition available.
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- Definition Retirement Of Leased Aircraft No definition available.
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- Definition Short-term Investments No definition available.
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- Definition Third Party Business Policy No definition available.
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- Definition Ticket Taxes No definition available.
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- References No definition available.
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- Definition Disclosure of accounting policy for advertising costs. For those costs that cannot be capitalized, discloses whether such costs are expensed as incurred or the first period in which the advertising takes place. For direct response advertising costs that are capitalized, describes those assets and the accounting policy used, including a description of the qualifying activity, the types of costs capitalized and the related amortization period. An entity also may disclose its accounting policy for cooperative advertising arrangements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of accounting policy for cash and cash equivalents, including the policy for determining which items are treated as cash equivalents. Other information that may be disclosed includes (1) the nature of any restrictions on the entity's use of its cash and cash equivalents, (2) whether the entity's cash and cash equivalents are insured or expose the entity to credit risk, (3) the classification of any negative balance accounts (overdrafts), and (4) the carrying basis of cash equivalents (for example, at cost) and whether the carrying amount of cash equivalents approximates fair value. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of accounting policy for frequent flier or other similar programs provided by the entity. No definition available.
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- Definition Disclosure of accounting policy for intangible assets. This accounting policy may address both intangible assets subject to amortization and those that are not. The following also may be disclosed: (1) a description of intangible assets (2) the estimated useful lives of those assets (3) the amortization method used (4) how the entity assesses and measures impairment of such assets (5) how future cash flows are estimated (6) how the fair values of such asset are determined. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of accounting policy for recognizing and measuring the impairment of long-lived assets. An entity also may disclose its accounting policy for long-lived assets to be sold. This policy excludes goodwill and intangible assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of accounting policy for tax positions taken in the tax return filed or to be filed for which it is more likely than not that the tax position will not be sustained upon examination by taxing authorities and other types of contingencies related to income taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of the accounting policy for maintenance costs. Does not include planned major maintenance activities. No definition available.
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- Definition Disclosure of accounting policy pertaining to new accounting pronouncements that may impact the entity's financial reporting. Includes, but is not limited to, quantification of the expected or actual impact. No definition available.
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- Definition Disclosure of accounting policy for long-lived, physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, basis of assets, depreciation and depletion methods used, including composite deprecation, estimated useful lives, capitalization policy, accounting treatment for costs incurred for repairs and maintenance, capitalized interest and the method it is calculated, disposals and impairments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of accounting policy for trade and other accounts receivable, and finance, loan and lease receivables, including those classified as held for investment and held for sale. This disclosure may include (1) the basis at which such receivables are carried in the entity's statements of financial position (2) how the level of the valuation allowance for receivables is determined (3) when impairments, charge-offs or recoveries are recognized for such receivables (4) the treatment of origination fees and costs, including the amortization method for net deferred fees or costs (5) the treatment of any premiums or discounts or unearned income (6) the entity's income recognition policies for such receivables, including those that are impaired, past due or placed on nonaccrual status and (7) the treatment of foreclosures or repossessions (8) the nature and amount of any guarantees to repurchase receivables. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of accounting policy for revenue recognition. If the entity has different policies for different types of revenue transactions, the policy for each material type of transaction is generally disclosed. If a sales transaction has multiple element arrangements (for example, delivery of multiple products, services or the rights to use assets) the disclosure may indicate the accounting policy for each unit of accounting as well as how units of accounting are determined and valued. The disclosure may encompass important judgment as to appropriateness of principles related to recognition of revenue. The disclosure also may indicate the entity's treatment of any unearned or deferred revenue that arises from the transaction. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of accounting policy for stock option and stock incentive plans. This disclosure may include (1) the types of stock option or incentive plans sponsored by the entity (2) the groups that participate in (or are covered by) each plan (3) significant plan provisions and (4) how stock compensation is measured, and the methodologies and significant assumptions used to determine that measurement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Disclosure of accounting policy for the use of estimates in the preparation of financial statements in conformity with generally accepted accounting principles. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Significant Accounting Policies (Tables) |
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Dec. 31, 2018 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Operating Revenue by Principal Geographic Region | The Company's operating revenue by principal geographic region (as defined by the U.S. Department of Transportation) for the years ended December 31 is presented in the table below (in millions):
(1) Amounts adjusted due to the adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606). See (u) below for additional information. |
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| Roll Forward of Frequent Flyer Deferred Revenue | The table below presents a roll forward of Frequent flyer deferred revenue (in millions):
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| Impact of the Adoption of the New Revenue Standard and the New Retirement Standard and the Expected Impact of the Adoption of the New Lease Standard | The adoption of the New Lease Standard is expected to impact our reported results as shown in the tables below (in millions, except per share amounts):
(a) Finance leases, under the New Lease Standard, are the equivalent of capital leases under Topic 840. The tables below present the impact of the adoption of the New Revenue Standard and the New Retirement Standard on select accounts and captions of UAL's statements of consolidated operations for the twelve months ended December 31, 2017 and 2016 (in millions, except per share amounts) and the impact on UAL's balance sheet accounts and captions as of December 31, 2017 (in millions):
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| Reconciliation of Cash, Cash Equivalents and Restricted Cash | The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the consolidated balance sheets that sum to the total of the same such amounts shown in the statements of consolidated cash flows (in millions):
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| Reconciliation of Cash, Cash Equivalents and Restricted Cash | The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the consolidated balance sheets that sum to the total of the same such amounts shown in the statements of consolidated cash flows (in millions):
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| Estimated Useful Lives of Property and Equipment | The estimated useful lives of property and equipment are as follows:
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| X | ||||||||||
- Definition Tabular disclosure of the type of arrangements and the corresponding amounts that comprise the current and noncurrent balance of deferred revenue as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of disaggregation of revenue into categories depicting how nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factor. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, balances by class of assets, depreciation and depletion expense and method used, including composite depreciation, and accumulated deprecation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of the components of cash and cash equivalents. No definition available.
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| X | ||||||||||
- Definition Tabular disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of cash and cash equivalents restricted as to withdrawal or usage. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Goodwill and Other Intangible Assets (Tables) |
12 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Dec. 31, 2018 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Goodwill and Intangible Assets Disclosure [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Information about Goodwill and Other Intangible Assets | The following table presents information about the Company's goodwill and other intangible assets at December 31 (in millions):
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- References No definition available.
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| X | ||||||||||
- Definition Tabular disclosure of goodwill and intangible assets, which may be broken down by segment or major class. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Earnings Per Share (Tables) |
12 Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Dec. 31, 2018 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Earnings Per Share [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Computation of Earnings Per Share | The computations of UAL's basic and diluted earnings per share are set forth below for the years ended December 31 (in millions, except per share amounts):
(a) Amounts adjusted due to the adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606). See Note 1 to the financial statements contained in Part II, Item 8 of this report for additional information. |
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Tabular disclosure of an entity's basic and diluted earnings per share calculations, including a reconciliation of numerators and denominators of the basic and diluted per-share computations for income from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Share-Based Compensation Plans (Tables) |
12 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Information Related to Share-Based Compensation Plan Cost | The following table provides information related to UAL's share-based compensation plan cost for the years ended December 31 (in millions):
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| Summary of Unearned Compensation and Weighted-Average Remaining Period to Recognize Costs | The table below summarizes UAL's unearned compensation and weighted-average remaining period to recognize costs for all outstanding share-based awards that are probable of being achieved as of December 31, 2018 (in millions, except as noted):
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| Summary of RSU and Restricted Stock Activity | The table below summarizes UAL's RSUs and restricted stock activity for the years ended December 31 (shares in millions):
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- References No definition available.
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- Definition Tabular disclosure of the amount of total share-based compensation cost, including the amounts attributable to each share-based compensation plan and any related tax benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Disclosure of the number and weighted-average grant date fair value for restricted stock and restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock and restricted stock units that were granted, vested, or forfeited during the year. No definition available.
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| X | ||||||||||
- Definition Tabular disclosure of the total compensation cost related to nonvested awards not yet recognized and the weighted-average period over which it is expected to be recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Accumulated Other Comprehensive Income (Loss) (Tables) |
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| Equity [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Components of AOCI | The tables below present the components of the Company's AOCI, net of tax (in millions):
(a) Prior service credits decreased by $3 million, $0 million and increased by $30 million and actuarial losses decreased by approximately $380 million, and increased $306 million and $560 million for 2018, 2017 and 2016, respectively. (b) This amount represents the reclassification from AOCI to RE of the stranded tax effects resulting from the enactment of the Tax Cuts and Jobs Act (the "Tax Act"). (c) This AOCI component is included in the computation of net periodic pension and other postretirement costs (see Note 8 of this report for additional information). |
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- References No definition available.
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- Definition Tabular disclosure of the components of accumulated other comprehensive income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Income Taxes (Tables) |
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| Income Tax Disclosure [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Income Tax Provision (Benefit) Differed from Amounts Computed at the Statutory Federal Income Tax Rate and Significant Components | The income tax provision (benefit) differed from amounts computed at the statutory federal income tax rate and consisted of the following significant components, as follows (in millions):
(a) Amounts adjusted due to the adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606). See Note 1 to the financial statements contained in Part II, Item 8 of this report for additional information. (b) Prior to the release of the deferred income tax valuation allowance in the third quarter of 2015, the Company recorded approximately $465 million of valuation allowance adjustments in AOCI. Subsequent to the release of the deferred income tax valuation allowance in 2015, the $465 million debit remained within AOCI, of which $180 million related to losses on fuel hedges designated for hedge accounting and $285 million related to pension and other postretirement liabilities. Accounting rules required the adjustments to remain in AOCI as long as the Company had fuel derivatives designated for cash flow hedge accounting and the Company continues to provide pension and postretirement benefits. In 2016, the Company settled all of its fuel hedges and has not entered into any new fuel derivative contracts for hedge accounting. Accordingly, the Company reclassified the $180 million to income tax expense in 2016. |
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| Temporary Differences and Carryforwards Giving Rise to Deferred Tax Assets and Liabilities | Temporary differences and carryforwards that give rise to deferred tax assets and liabilities at December 31, 2018 and 2017 were as follows (in millions):
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- References No definition available.
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- Definition Tabular disclosure of the components of net deferred tax asset or liability recognized in an entity's statement of financial position, including the following: the total of all deferred tax liabilities, the total of all deferred tax assets, the total valuation allowance recognized for deferred tax assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Tabular disclosure of the reconciliation using percentage or dollar amounts of the reported amount of income tax expense attributable to continuing operations for the year to the amount of income tax expense that would result from applying domestic federal statutory tax rates to pretax income from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Pension and Other Postretirement Plans (Tables) |
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| Retirement Benefits [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Reconciliation of the Change in Benefit Obligation and Plan Assets and Funded Status | The following tables set forth the reconciliation of the beginning and ending balances of the benefit obligation and plan assets, the funded status and the amounts recognized in these financial statements for the defined benefit and other postretirement plans (in millions):
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| Amounts Recognized in Consolidated Balance Sheet and Accumulated Other Comprehensive Income (Loss) |
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| Accumulated Benefit Obligation and Projected Benefit Obligation in Excess of Plan Assets | The following information relates to all pension plans with an accumulated benefit obligation and a projected benefit obligation in excess of plan assets at December 31 (in millions):
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| Components Of Net Periodic Benefit Cost | Net periodic benefit cost for the years ended December 31 included the following components (in millions):
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| Assumptions Used for Benefit Plans | The assumptions used for the benefit plans were as follows:
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| Allocation of Plan Assets | United's plan assets are allocated within the following guidelines:
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| Pension and Other Postretirement Plan Assets | The following tables present information about United's pension and other postretirement plan assets at December 31, (in millions):
(a) In accordance with the relevant accounting standards, certain investments that are measured at fair value using the net asset value ("NAV") per share (or its equivalent) have not been classified in the fair value hierarchy. These investments are commingled funds that invest in fixed-income instruments including bonds, debt securities, and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. Redemption periods for these investments range from daily to semiannually. |
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| Defined Benefit Plan Assets Measured at Fair Value Using Unobservable Inputs | The reconciliation of United's defined benefit plan assets measured at fair value using unobservable inputs (Level 3) for the years ended December 31, 2018 and 2017 is as follows (in millions):
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| Estimated Future Benefit Payments | The estimated future benefit payments, net of expected participant contributions, in United's pension plans and other postretirement benefit plans as of December 31, 2018 are as follows (in millions):
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| Participation in the IAM National Pension Plan | United's participation in the IAM National Pension Plan ("IAM Plan") for the annual period ended December 31, 2018 is outlined in the table below. There have been no significant changes that affect the comparability of 2018 and 2017 contributions. The risks of participating in these multi-employer plans are different from single-employer plans, as United may be subject to additional risks that others do not meet their obligations, which in certain circumstances could revert to United. The IAM Plan reported $435 million in employers' contributions for the year ended December 31, 2017. For 2017, the Company's contributions to the IAM Plan represented more than 5% of total contributions to the IAM Plan. The 2018 information is not available as Form 5500 is not final for the plan year.
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- References No definition available.
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| X | ||||||||||
- Definition Tabular disclosure of accumulated benefit obligations and fair values of plan assets of pension plans and/or other employee benefit plans where the accumulated benefit obligation exceeds the fair value of plan assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of the major categories of plan assets of pension plans and/or other employee benefit plans. This information may include, but is not limited to, the target allocation of plan assets, the fair value of each major category of plan assets, and the level within the fair value hierarchy in which the fair value measurements fall. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of the amounts that are recognized in the balance sheet (or statement of financial position) for pension plans and/or other employee benefit plans, showing separately the assets and current and noncurrent liabilities (if applicable) recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of the assumptions used to determine for pension plans and/or other employee benefit plans the benefit obligation and net benefit cost, including assumed discount rates, rate increase in compensation increase, and expected long-term rates of return on plan assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of one or more of the entity's defined benefit pension plans or one or more other defined benefit postretirement plans, separately for pension plans and other postretirement benefit plans including the entity's schedule of fair value of plan assets for defined benefit or other postretirement plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of the effect of fair value measurements using significant unobservable inputs (Level 3) on changes in plan assets of pension plans and/or other employee benefit plans for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of benefits expected to be paid by pension plans and/or other employee benefit plans in each of the next five fiscal years and in the aggregate for the five fiscal years thereafter. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of the quantitative and qualitative information related to multiemployer plans in which the employer participates. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of the components of net benefit costs for pension plans and/or other employee benefit plans including service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) recognized due to settlements or curtailments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of net funded status of pension plans and/or other employee benefit plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Investments and Fair Value Measurements (Tables) |
12 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Dec. 31, 2018 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Fair Value Disclosures [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Financial Assets and Liabilities Measured at Fair Value on Recurring Basis | The table below presents disclosures about the fair value of financial assets and liabilities measured at fair value on a recurring basis in the Company's financial statements as of December 31 (in millions):
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| Carrying Values and Estimated Fair Values of Financial Instruments | The table below presents the carrying values and estimated fair values of financial instruments not presented in the tables above as of December 31 (in millions). Carrying amounts include any related discounts, premiums, issuance costs and origination costs:
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| X | ||||||||||
- Definition Tabular disclosure of the fair value of financial instruments, including financial assets and financial liabilities, and the measurements of those instruments, assets, and liabilities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Debt (Tables) |
12 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Dec. 31, 2018 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Debt Disclosure [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Summary of Long-Term Debt |
(a) UAL is the issuer of this debt. United is a guarantor. |
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| Contractual Principal Payments under Outstanding Long-Term Debt Agreements | The table below presents the Company's contractual principal payments (not including debt discount or debt issuance costs) at December 31, 2018 under then-outstanding long-term debt agreements in each of the next five calendar years (in millions):
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| Details of Pass Through Trusts | Certain details of the pass-through trusts with proceeds received from issuance of debt in 2018 are as follows (in millions, except stated interest rate):
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| Summary of Collateral Covenants and Cross Default Provisions | The collateral, covenants and cross default provisions of the Company's principal debt instruments that contain such provisions are summarized in the table below:
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| X | ||||||||||
- Definition Schedule of Debt Instruments Pass Through Trusts No definition available.
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| X | ||||||||||
- Definition Schedule of Financial Covenants No definition available.
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Tabular disclosure of long-debt instruments or arrangements, including identification, terms, features, collateral requirements and other information necessary to a fair presentation. These are debt arrangements that originally required repayment more than twelve months after issuance or greater than the normal operating cycle of the entity, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of the combined aggregate amount of maturities and sinking fund requirements for all long-term borrowings for each of the five years following the date of the latest balance sheet date presented. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Leases and Capacity Purchase Agreements (Tables) |
12 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Dec. 31, 2018 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Leases [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Future Minimum Lease Payments for Capital and Operating Leases | At December 31, 2018, United's scheduled future minimum lease payments under operating leases having initial or remaining noncancelable lease terms of more than one year, aircraft leases, including aircraft rent under CPAs and capital leases (substantially all of which are for aircraft) were as follows (in millions):
(a) Includes fair value lease and deferred financing fee balances, which are being amortized over the terms of their respective leases. (b) Includes airport construction projects managed by United in which United has construction risk, including project cost overruns. The Company recorded an asset for project costs and a related liability equal to project costs funded by parties other than United. As of December 31, 2018, United had an asset balance of $886 million recorded in operating property and equipment and $920 million recorded in current and long-term obligations under capital leases for these airport construction projects. |
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| Future Lease Payment Under Terms of Capacity Purchase Agreement | Based on these assumptions as of December 31, 2018, our future payments through the end of the terms of our CPAs are presented in the table below (in billions):
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| X | ||||||||||
- Definition Future Lease Payment Terms For Capacity Purchase Agreement No definition available.
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| X | ||||||||||
- Definition Schedule Of Future Minimum Lease Payments For Capital And Operating Leases. No definition available.
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| X | ||||||||||
- References No definition available.
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Commitments and Contingencies (Tables) |
12 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Dec. 31, 2018 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Commitments and Contingencies Disclosure [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Summary of Commitments to Purchase Aircraft | The table below summarizes United's commitments as of December 31, 2018, which primarily relate to the acquisition of aircraft and related spare engines, aircraft improvements and include other capital purchase commitments for the years ended December 31 (in billions). Any new firm aircraft orders, including through the exercise of purchase options and purchase rights, will increase the total future capital commitments of the Company.
As of December 31, 2018, United had firm commitments and options to purchase aircraft from The Boeing Company ("Boeing"), Airbus S.A.S. ("Airbus") and Embraer S.A. ("Embraer") presented in the table below:
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Tabular disclosure of key provisions of an arrangement under which the entity has agreed to purchase goods or services over a period of time greater than one year or the normal operating cycle, if longer, including the item for which expenditures will be made, minimum quantities, milestones, time period and committed amount. No definition available.
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Special Charges (Tables) |
12 Months Ended | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Dec. 31, 2018 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Business Combinations [Abstract] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Components of Special Charges | Special charges in the statements of consolidated operations consisted of the following for the years ended December 31 (in millions):
(a) Amounts adjusted due to the adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606) and Accounting Standards Update No. 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost. See Note 1 to the financial statements contained in Part II, Item 8 of this report for additional information. |
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| Activity Related to the Accruals for Severance and Medical Costs and Future Lease Payments | Activity related to the accruals for severance and medical costs and future lease payments on permanently grounded aircraft is as follows (in millions):
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- References No definition available.
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| X | ||||||||||
- Definition Tabular disclosure of costs incurred for restructuring including, but not limited to, exit and disposal activities, remediation, implementation, integration, asset impairment, and charges against earnings from the write-down of assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Tabular disclosure of an entity's restructuring reserve that occurred during the period associated with the exit from or disposal of business activities or restructurings for each major type of cost. This element may also include a description of any reversal and other adjustment made during the period to the amount of an accrued liability for restructuring activities. This element may be used to encapsulate the roll forward presentations of an entity's restructuring reserve by type of cost and in total, and explanation of changes that occurred in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Selected Quarterly Financial Data (Unaudited) (Tables) |
12 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Dec. 31, 2018 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Quarterly Financial Information Disclosure [Abstract] | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Summary of Selected Quarterly Financial Data |
(a) Amounts adjusted due to the adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606) and Accounting Standards Update No. 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost. See Note 1 to the financial statements contained in Part II, Item 8 of this report for additional information. |
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| Impact of Significant Items on Quarterly Results |
(a) Amounts adjusted due to the adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606) and Accounting Standards Update No. 2017-07, Improving the Presentation of Net Periodic Pension Cost and Net Periodic Postretirement Benefit Cost. See Note 1 to the financial statements contained in Part II, Item 8 of this report for additional information. UAL's quarterly financial data is subject to seasonal fluctuations and historically its second and third quarter financial results, which reflect higher travel demand, are better than its first and fourth quarter financial results. UAL's quarterly results were impacted by the following significant items (in millions):
(a) Amounts adjusted due to the adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606). See Note 1 to the financial statements contained in Part II, Item 8 of this report for additional information. |
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| X | ||||||||||
- Definition Schedule Of Quarterly Reporting Table. No definition available.
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Tabular disclosure of quarterly financial data. Includes, but is not limited to, financial information for fiscal quarters, cumulative effect of a change in accounting principle and earnings per share data. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Significant Accounting Policies - Operating Revenue by Principal Geographic Region (Details) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|||||
| Disaggregation of Revenue [Line Items] | |||||||||||||||
| Revenue | $ 10,491 | $ 11,003 | $ 10,777 | $ 9,032 | $ 9,451 | $ 9,899 | $ 10,008 | $ 8,426 | $ 41,303 | $ 37,784 | [1] | $ 36,558 | [1] | ||
| Domestic (U.S. and Canada) | |||||||||||||||
| Disaggregation of Revenue [Line Items] | |||||||||||||||
| Revenue | 25,552 | 23,114 | 22,151 | ||||||||||||
| Atlantic | |||||||||||||||
| Disaggregation of Revenue [Line Items] | |||||||||||||||
| Revenue | 7,103 | 6,340 | 6,194 | ||||||||||||
| Pacific | |||||||||||||||
| Disaggregation of Revenue [Line Items] | |||||||||||||||
| Revenue | 5,188 | 4,914 | 4,984 | ||||||||||||
| Latin America | |||||||||||||||
| Disaggregation of Revenue [Line Items] | |||||||||||||||
| Revenue | $ 3,460 | $ 3,416 | $ 3,229 | ||||||||||||
| |||||||||||||||
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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| X | ||||||||||
- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Details
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| X | ||||||||||
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| X | ||||||||||
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| X | ||||||||||
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Significant Accounting Policies - Narrative (Details) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Jan. 01, 2018 |
Jan. 01, 2017 |
|||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Revenue | $ 10,491 | $ 11,003 | $ 10,777 | $ 9,032 | $ 9,451 | $ 9,899 | $ 10,008 | $ 8,426 | $ 41,303 | $ 37,784 | [1] | $ 36,558 | [1] | ||||
| Period of member account inactivity at which miles expire | 18 months | ||||||||||||||||
| Carrying value of computer software | $ 359 | $ 345 | $ 359 | 345 | |||||||||||||
| Residual value | 10.00% | 10.00% | |||||||||||||||
| Advertising expense | $ 211 | 217 | 220 | ||||||||||||||
| Reclassification to retained earnings upon adoption of accounting standard | $ (14) | ||||||||||||||||
| Retained Earnings (Accumulated Deficit) | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Reclassification to retained earnings upon adoption of accounting standard | $ 6 | $ (14) | |||||||||||||||
| ASU 2016-01 | Retained Earnings (Accumulated Deficit) | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Reclassification to retained earnings upon adoption of accounting standard | $ 6 | ||||||||||||||||
| Minimum | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Frequent flier program expiration period | 1 year | ||||||||||||||||
| Maximum | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Frequent flier program expiration period | 8 years | ||||||||||||||||
| Aircraft Seats | Minimum | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Estimated useful life | 10 years | ||||||||||||||||
| Aircraft Seats | Maximum | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Estimated useful life | 15 years | ||||||||||||||||
| Aircraft and Aircraft Spare Parts | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Residual value | 10.00% | 10.00% | |||||||||||||||
| Computer Software | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Depreciation expense | $ 122 | 117 | 108 | ||||||||||||||
| Computer Software | Minimum | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Estimated useful life | 5 years | ||||||||||||||||
| Computer Software | Maximum | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Estimated useful life | 15 years | ||||||||||||||||
| Passenger Revenue | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Ancillary fees | $ 2,200 | 2,000 | 1,900 | ||||||||||||||
| Passenger Revenue | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Revenue | 37,706 | 34,460 | [1] | 33,429 | [1] | ||||||||||||
| Other Operating Revenue | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Revenue | 2,360 | 2,210 | [1] | 2,195 | [1] | ||||||||||||
| Other Operating Revenue | Chase and Other Partner Agreements | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Revenue | 2,000 | 1,800 | $ 1,700 | ||||||||||||||
| Transportation Advance Ticket Arrangement | Passenger Revenue | |||||||||||||||||
| Summary Of Significant Accounting Policies [Line Items] | |||||||||||||||||
| Revenue | $ 3,100 | $ 2,900 | |||||||||||||||
| |||||||||||||||||
| X | ||||||||||
- Definition Ancillary fees. No definition available.
|
| X | ||||||||||
- Definition Frequent flyer mileage program expiration period. No definition available.
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| X | ||||||||||
- Definition Frequent flyer mileage program expiration period after member account inactivity. No definition available.
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| X | ||||||||||
- Definition Summary Of Significant Accounting Policies [Line Items] No definition available.
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| X | ||||||||||
- Definition Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption. No definition available.
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| X | ||||||||||
- Definition The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Stated as a percentage, the estimated or actual value of the asset at the end of its useful life or when it is no longer serviceable (cannot be used for its original purpose) divided by its [historical] capitalized cost. No definition available.
|
| X | ||||||||||
- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. No definition available.
|
| X | ||||||||||
- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
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| X | ||||||||||
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| X | ||||||||||
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| X | ||||||||||
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| X | ||||||||||
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| X | ||||||||||
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| X | ||||||||||
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| X | ||||||||||
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| X | ||||||||||
- Details
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Significant Accounting Policies - Impact of the Adoption of the New Revenue Standard and the New Retirement Standard (Details) - USD ($) $ / shares in Units, $ in Millions |
3 Months Ended | 12 Months Ended | ||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | $ 10,491 | $ 11,003 | $ 10,777 | $ 9,032 | $ 9,451 | $ 9,899 | $ 10,008 | $ 8,426 | $ 41,303 | $ 37,784 | [1] | $ 36,558 | [1] | |||||||||||
| Operating expenses | 38,011 | 34,113 | [1] | 32,214 | [1] | |||||||||||||||||||
| Operating income | 652 | 1,203 | 1,161 | 276 | 776 | 1,138 | 1,437 | 320 | 3,292 | 3,671 | [1] | 4,344 | [1] | |||||||||||
| Total nonoperating expense, net | (634) | (631) | [1] | (571) | [1] | |||||||||||||||||||
| Income before income taxes | 2,658 | 3,040 | [1] | 3,773 | [1] | |||||||||||||||||||
| Income tax expense | 529 | 896 | [1] | 1,539 | [1] | |||||||||||||||||||
| Net income | $ 462 | $ 836 | $ 684 | $ 147 | $ 579 | $ 645 | $ 821 | $ 99 | $ 2,129 | $ 2,144 | [1],[2],[3],[4] | $ 2,234 | [1],[2],[3],[4] | |||||||||||
| Earnings per share, basic (in dollars per share) | $ 1.71 | $ 3.07 | $ 2.49 | $ 0.52 | $ 1.99 | $ 2.15 | $ 2.67 | $ 0.32 | $ 7.73 | $ 7.08 | [1] | $ 6.77 | [1] | |||||||||||
| Earnings per share, diluted (in dollars per share) | $ 1.70 | $ 3.06 | $ 2.48 | $ 0.52 | $ 1.98 | $ 2.15 | $ 2.67 | $ 0.32 | $ 7.70 | $ 7.06 | [1] | $ 6.76 | [1] | |||||||||||
| Current assets: | ||||||||||||||||||||||||
| Prepaid expenses and other | $ 913 | $ 1,071 | [5] | $ 913 | $ 1,071 | [5] | ||||||||||||||||||
| Current liabilities: | ||||||||||||||||||||||||
| Advance ticket sales | 4,381 | 3,940 | [5] | 4,381 | 3,940 | [5] | ||||||||||||||||||
| Frequent flyer deferred revenue | 2,286 | 2,192 | [5] | 2,286 | 2,192 | [5] | ||||||||||||||||||
| Other | 619 | 576 | [5] | 619 | 576 | [5] | ||||||||||||||||||
| Other liabilities and deferred credits: | ||||||||||||||||||||||||
| Frequent flyer deferred revenue | 2,719 | 2,591 | [5] | 2,719 | 2,591 | [5] | ||||||||||||||||||
| Deferred income taxes | 814 | 204 | [5] | 814 | 204 | [5] | ||||||||||||||||||
| Stockholders' equity: | ||||||||||||||||||||||||
| Retained earnings | $ 6,668 | 4,549 | [5] | 6,668 | 4,549 | [5] | ||||||||||||||||||
| As Previously Reported | ||||||||||||||||||||||||
| Current assets: | ||||||||||||||||||||||||
| Prepaid expenses and other | 1,051 | 1,051 | ||||||||||||||||||||||
| Current liabilities: | ||||||||||||||||||||||||
| Advance ticket sales | 3,876 | 3,876 | ||||||||||||||||||||||
| Frequent flyer deferred revenue | 2,176 | 2,176 | ||||||||||||||||||||||
| Other | 569 | 569 | ||||||||||||||||||||||
| Other liabilities and deferred credits: | ||||||||||||||||||||||||
| Frequent flyer deferred revenue | 2,565 | 2,565 | ||||||||||||||||||||||
| Deferred income taxes | 225 | 225 | ||||||||||||||||||||||
| Stockholders' equity: | ||||||||||||||||||||||||
| Retained earnings | 4,621 | 4,621 | ||||||||||||||||||||||
| Passenger revenue | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | 37,706 | 34,460 | [1] | $ 33,429 | [1] | |||||||||||||||||||
| Cargo | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | 1,237 | 1,114 | [1] | 934 | [1] | |||||||||||||||||||
| Other operating revenue | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | $ 2,360 | 2,210 | [1] | 2,195 | [1] | |||||||||||||||||||
| As Previously Reported | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | 37,736 | 36,556 | ||||||||||||||||||||||
| Operating expenses | 34,238 | 32,218 | ||||||||||||||||||||||
| Operating income | 3,498 | 4,338 | ||||||||||||||||||||||
| Total nonoperating expense, net | (499) | (519) | ||||||||||||||||||||||
| Income before income taxes | 2,999 | 3,819 | ||||||||||||||||||||||
| Income tax expense | 868 | 1,556 | ||||||||||||||||||||||
| Net income | $ 2,131 | $ 2,263 | ||||||||||||||||||||||
| Earnings per share, basic (in dollars per share) | $ 7.04 | $ 6.86 | ||||||||||||||||||||||
| Earnings per share, diluted (in dollars per share) | $ 7.02 | $ 6.85 | ||||||||||||||||||||||
| As Previously Reported | Passenger revenue | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | $ 32,404 | $ 31,457 | ||||||||||||||||||||||
| As Previously Reported | Cargo | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | 1,035 | 876 | ||||||||||||||||||||||
| As Previously Reported | Other operating revenue | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | 4,297 | 4,223 | ||||||||||||||||||||||
| ASU 2014-09 | New Revenue Standard Adjustments | ||||||||||||||||||||||||
| Current assets: | ||||||||||||||||||||||||
| Prepaid expenses and other | 20 | 20 | ||||||||||||||||||||||
| Current liabilities: | ||||||||||||||||||||||||
| Advance ticket sales | 64 | 64 | ||||||||||||||||||||||
| Frequent flyer deferred revenue | 16 | 16 | ||||||||||||||||||||||
| Other | 7 | 7 | ||||||||||||||||||||||
| Other liabilities and deferred credits: | ||||||||||||||||||||||||
| Frequent flyer deferred revenue | 26 | 26 | ||||||||||||||||||||||
| Deferred income taxes | (21) | (21) | ||||||||||||||||||||||
| Stockholders' equity: | ||||||||||||||||||||||||
| Retained earnings | $ (72) | (72) | ||||||||||||||||||||||
| ASU 2014-09 | Adjustment | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | 48 | 2 | ||||||||||||||||||||||
| Operating expenses | (21) | (12) | ||||||||||||||||||||||
| Operating income | 69 | 14 | ||||||||||||||||||||||
| Total nonoperating expense, net | (28) | (60) | ||||||||||||||||||||||
| Income before income taxes | 41 | (46) | ||||||||||||||||||||||
| Income tax expense | 28 | (17) | ||||||||||||||||||||||
| Net income | $ 13 | $ (29) | ||||||||||||||||||||||
| Earnings per share, basic (in dollars per share) | $ 0.04 | $ (0.09) | ||||||||||||||||||||||
| Earnings per share, diluted (in dollars per share) | $ 0.04 | $ (0.09) | ||||||||||||||||||||||
| ASU 2014-09 | Adjustment | Passenger revenue | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | $ 2,056 | $ 1,972 | ||||||||||||||||||||||
| ASU 2014-09 | Adjustment | Cargo | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | 79 | 58 | ||||||||||||||||||||||
| ASU 2014-09 | Adjustment | Other operating revenue | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | (2,087) | (2,028) | ||||||||||||||||||||||
| ASU 2017-07 | Adjustment | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | 0 | 0 | ||||||||||||||||||||||
| Operating expenses | (104) | 8 | ||||||||||||||||||||||
| Operating income | 104 | (8) | ||||||||||||||||||||||
| Total nonoperating expense, net | (104) | 8 | ||||||||||||||||||||||
| Income before income taxes | 0 | 0 | ||||||||||||||||||||||
| Income tax expense | 0 | 0 | ||||||||||||||||||||||
| Net income | $ 0 | $ 0 | ||||||||||||||||||||||
| Earnings per share, basic (in dollars per share) | $ 0.00 | $ 0.00 | ||||||||||||||||||||||
| Earnings per share, diluted (in dollars per share) | $ 0.00 | $ 0.00 | ||||||||||||||||||||||
| ASU 2017-07 | Adjustment | Passenger revenue | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | $ 0 | $ 0 | ||||||||||||||||||||||
| ASU 2017-07 | Adjustment | Cargo | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | 0 | 0 | ||||||||||||||||||||||
| ASU 2017-07 | Adjustment | Other operating revenue | ||||||||||||||||||||||||
| Operating revenue: | ||||||||||||||||||||||||
| Revenue | $ 0 | $ 0 | ||||||||||||||||||||||
| ||||||||||||||||||||||||
| X | ||||||||||
- Definition Amount of liabilities incurred to vendors for goods and services received, and accrued liabilities classified as other, payable within one year or the normal operating cycle, if longer. No definition available.
|
| X | ||||||||||
- Definition The value of air transportation services sold but as yet unused by the passenger, including sales for air transportation to be provided by the reporting air carrier and air transportation to be provided by another air carrier for whom sales were made. Used to reflect the current portion of the liability (within one year or within the normal operating cycle if longer). No definition available.
|
| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Total costs of sales and operating expenses for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Value of revenue deferred or cost to provide future products or services, primarily air transportation, associated with programs used by airlines to encourage passenger loyalty by providing rewards geared to the frequency of travel on the sponsoring airline, typically in the form of frequent flyer miles, points, or segments that can be accumulated and converted into free or discounted travel or other redemption options. Used to reflect the current portion of the liability (within one year or within the normal operating cycle if longer). No definition available.
|
| X | ||||||||||
- Definition Value of revenue deferred or cost to provide future products or services, primarily air transportation, associated with programs used by airlines to encourage passenger loyalty by providing rewards geared to the frequency of travel on the sponsoring airline, typically in the form of frequent flyer miles, points, or segments that can be accumulated and converted into free or discounted travel or other redemption options. Used to reflect the noncurrent portion of the liability. No definition available.
|
| X | ||||||||||
- Definition Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The net result for the period of deducting operating expenses from operating revenues. No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cumulative amount of the reporting entity's undistributed earnings or deficit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
|
Significant Accounting Policies - Roll Forward of Frequent Flier Deferred Revenue (Details) - Transportation Advance Ticket Arrangement - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
|
| Movement in Deferred Revenue [Roll Forward] | ||
| Total Frequent flyer deferred revenue - beginning balance | $ 4,783 | $ 4,889 |
| Total miles awarded | 2,451 | 2,077 |
| Travel miles redeemed (Passenger revenue) | (2,068) | (2,004) |
| Non-travel miles redeemed (Other operating revenue) | (161) | (179) |
| Total Frequent flyer deferred revenue - ending balance | $ 5,005 | $ 4,783 |
| X | ||||||||||
- Definition Frequent flyer mileage miles awarded in period. No definition available.
|
| X | ||||||||||
- Definition Non-travel miles redemption, frequent flyer deferred revenue. No definition available.
|
| X | ||||||||||
- Definition Travel miles redemption, frequent flyer deferred revenue. No definition available.
|
| X | ||||||||||
- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
|
| X | ||||||||||
- Details
|
Significant Accounting Policies - Estimated Useful Lives of Property and Equipment (Details) |
12 Months Ended |
|---|---|
Dec. 31, 2018 | |
| Aircraft and related rotable parts | Minimum | |
| Property, Plant and Equipment [Line Items] | |
| Estimated useful life | 25 years |
| Aircraft and related rotable parts | Maximum | |
| Property, Plant and Equipment [Line Items] | |
| Estimated useful life | 30 years |
| Aircraft seats | Minimum | |
| Property, Plant and Equipment [Line Items] | |
| Estimated useful life | 10 years |
| Aircraft seats | Maximum | |
| Property, Plant and Equipment [Line Items] | |
| Estimated useful life | 15 years |
| Buildings | Minimum | |
| Property, Plant and Equipment [Line Items] | |
| Estimated useful life | 25 years |
| Buildings | Maximum | |
| Property, Plant and Equipment [Line Items] | |
| Estimated useful life | 45 years |
| Other property and equipment | Minimum | |
| Property, Plant and Equipment [Line Items] | |
| Estimated useful life | 3 years |
| Other property and equipment | Maximum | |
| Property, Plant and Equipment [Line Items] | |
| Estimated useful life | 15 years |
| Computer software | Minimum | |
| Property, Plant and Equipment [Line Items] | |
| Estimated useful life | 5 years |
| Computer software | Maximum | |
| Property, Plant and Equipment [Line Items] | |
| Estimated useful life | 15 years |
| Building improvements | Minimum | |
| Property, Plant and Equipment [Line Items] | |
| Estimated useful life | 1 year |
| Building improvements | Maximum | |
| Property, Plant and Equipment [Line Items] | |
| Estimated useful life | 40 years |
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. No definition available.
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| X | ||||||||||
- Details
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| X | ||||||||||
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| X | ||||||||||
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| X | ||||||||||
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| X | ||||||||||
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Significant Accounting Policies - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Millions |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Current assets: | |||||||||||||||
| Cash and cash equivalents | $ 1,694 | $ 1,482 | [1] | $ 2,179 | |||||||||||
| Other assets: | |||||||||||||||
| Restricted cash | 105 | 91 | [1] | 124 | |||||||||||
| Total cash, cash equivalents and restricted cash shown in the statement of consolidated cash flows | 1,799 | 1,591 | [2] | 2,303 | [2] | $ 3,212 | [2] | ||||||||
| Prepaid Expenses and Other | |||||||||||||||
| Current assets: | |||||||||||||||
| Restricted cash | 0 | 18 | 0 | ||||||||||||
| United Airlines, Inc. | |||||||||||||||
| Current assets: | |||||||||||||||
| Cash and cash equivalents | 1,688 | 1,476 | [3] | 2,173 | |||||||||||
| Other assets: | |||||||||||||||
| Restricted cash | 105 | 91 | [3] | 124 | |||||||||||
| Total cash, cash equivalents and restricted cash shown in the statement of consolidated cash flows | 1,793 | 1,585 | [4] | 2,297 | [4] | $ 3,206 | [4] | ||||||||
| United Airlines, Inc. | Prepaid Expenses and Other | |||||||||||||||
| Current assets: | |||||||||||||||
| Restricted cash | $ 0 | $ 18 | $ 0 | ||||||||||||
| |||||||||||||||
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
|
Significant Accounting Policies - Expected Impact of the Adoption of the New Lease Standard (Details) - USD ($) $ / shares in Units, $ in Millions |
3 Months Ended | 12 Months Ended | ||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
[2] | |||||||||||||
| Current assets: | ||||||||||||||||||||||||
| Receivables, less allowance for doubtful accounts (2018—$8; 2017—$7) | $ 1,346 | $ 1,340 | [1] | $ 1,346 | $ 1,340 | [1] | ||||||||||||||||||
| Prepaid expenses and other | 913 | 1,071 | [1] | 913 | 1,071 | [1] | ||||||||||||||||||
| Operating property and equipment: | ||||||||||||||||||||||||
| Other property and equipment | 7,919 | 6,946 | [1] | 7,919 | 6,946 | [1] | ||||||||||||||||||
| Less-Accumulated depreciation and amortization (owned) | (12,760) | (11,159) | [1] | (12,760) | (11,159) | [1] | ||||||||||||||||||
| Flight equipment | 1,029 | 1,151 | [1] | 1,029 | 1,151 | [1] | ||||||||||||||||||
| Less-Accumulated amortization | (654) | (777) | [1] | (654) | (777) | [1] | ||||||||||||||||||
| Current liabilities: | ||||||||||||||||||||||||
| Current maturities of capital leases | 149 | 128 | [1] | 149 | 128 | [1] | ||||||||||||||||||
| Other | 619 | 576 | [1] | 619 | 576 | [1] | ||||||||||||||||||
| Long-term obligations under finance leases | 1,134 | 996 | 1,134 | 996 | ||||||||||||||||||||
| Other liabilities and deferred credits: | ||||||||||||||||||||||||
| Deferred income taxes | 814 | 204 | [1] | 814 | 204 | [1] | ||||||||||||||||||
| Other | 1,832 | 1,832 | [1] | 1,832 | 1,832 | [1] | ||||||||||||||||||
| Stockholders' equity: | ||||||||||||||||||||||||
| Retained earnings | 6,668 | 4,549 | [1] | 6,668 | 4,549 | [1] | ||||||||||||||||||
| Operating expense: | ||||||||||||||||||||||||
| Regional capacity purchase | 2,601 | 2,232 | [2] | $ 2,197 | ||||||||||||||||||||
| Landing fees and other rent | 2,359 | 2,240 | [2] | 2,165 | ||||||||||||||||||||
| Depreciation and amortization | 2,240 | 2,149 | [2],[3] | 1,977 | [3] | |||||||||||||||||||
| Operating expenses | 38,011 | 34,113 | [2] | 32,214 | ||||||||||||||||||||
| Operating income | 652 | $ 1,203 | $ 1,161 | $ 276 | 776 | $ 1,138 | $ 1,437 | $ 320 | 3,292 | 3,671 | [2] | 4,344 | ||||||||||||
| Nonoperating income (expense): | ||||||||||||||||||||||||
| Interest expense | (729) | (671) | [2] | (674) | ||||||||||||||||||||
| Interest capitalized | 70 | 84 | [2] | 72 | ||||||||||||||||||||
| Total nonoperating expense, net | (634) | (631) | [2] | (571) | ||||||||||||||||||||
| Income before income taxes | 2,658 | 3,040 | [2] | 3,773 | ||||||||||||||||||||
| Income tax expense | 529 | 896 | [2] | 1,539 | ||||||||||||||||||||
| Net income | $ 462 | $ 836 | $ 684 | $ 147 | $ 579 | $ 645 | $ 821 | $ 99 | $ 2,129 | $ 2,144 | [2],[3],[4],[5] | $ 2,234 | [3],[4],[5] | |||||||||||
| Earnings per share, basic (in dollars per share) | $ 1.71 | $ 3.07 | $ 2.49 | $ 0.52 | $ 1.99 | $ 2.15 | $ 2.67 | $ 0.32 | $ 7.73 | $ 7.08 | [2] | $ 6.77 | ||||||||||||
| Earnings per share, diluted (in dollars per share) | $ 1.70 | $ 3.06 | $ 2.48 | $ 0.52 | $ 1.98 | $ 2.15 | $ 2.67 | $ 0.32 | $ 7.70 | $ 7.06 | [2] | $ 6.76 | ||||||||||||
| ASU 2016-02 | ||||||||||||||||||||||||
| Current assets: | ||||||||||||||||||||||||
| Receivables, less allowance for doubtful accounts (2018—$8; 2017—$7) | $ 1,426 | $ 1,466 | $ 1,426 | $ 1,466 | ||||||||||||||||||||
| Prepaid expenses and other | 733 | 863 | 733 | 863 | ||||||||||||||||||||
| Operating property and equipment: | ||||||||||||||||||||||||
| Other property and equipment | 6,878 | 6,024 | 6,878 | 6,024 | ||||||||||||||||||||
| Less-Accumulated depreciation and amortization (owned) | (12,620) | (11,067) | (12,620) | (11,067) | ||||||||||||||||||||
| Flight equipment (Finance leases) | 992 | 940 | 992 | 940 | ||||||||||||||||||||
| Less-Accumulated amortization | (646) | (608) | (646) | (608) | ||||||||||||||||||||
| Current liabilities: | ||||||||||||||||||||||||
| Current maturities of finance leases | 123 | 78 | 123 | 78 | ||||||||||||||||||||
| Current maturities of operating leases | 719 | 949 | 719 | 949 | ||||||||||||||||||||
| Other | 553 | 518 | 553 | 518 | ||||||||||||||||||||
| Long-term obligations under finance leases | 224 | 230 | 224 | 230 | ||||||||||||||||||||
| Long-term obligations under operating leases | 5,276 | 5,789 | 5,276 | 5,789 | ||||||||||||||||||||
| Other liabilities and deferred credits: | ||||||||||||||||||||||||
| Deferred income taxes | 828 | 220 | 828 | 220 | ||||||||||||||||||||
| Other | 1,010 | 1,021 | 1,010 | 1,021 | ||||||||||||||||||||
| Stockholders' equity: | ||||||||||||||||||||||||
| Retained earnings | 6,715 | 4,603 | 6,715 | 4,603 | ||||||||||||||||||||
| Operating expense: | ||||||||||||||||||||||||
| Regional capacity purchase | 2,649 | 2,268 | ||||||||||||||||||||||
| Landing fees and other rent | 2,449 | 2,310 | ||||||||||||||||||||||
| Depreciation and amortization | 2,165 | 2,096 | ||||||||||||||||||||||
| Operating expenses | 38,074 | 34,166 | ||||||||||||||||||||||
| Operating income | 3,229 | 3,618 | ||||||||||||||||||||||
| Nonoperating income (expense): | ||||||||||||||||||||||||
| Interest expense | (670) | (626) | ||||||||||||||||||||||
| Interest capitalized | 65 | 74 | ||||||||||||||||||||||
| Total nonoperating expense, net | (581) | (595) | ||||||||||||||||||||||
| Income before income taxes | 2,648 | 3,023 | ||||||||||||||||||||||
| Income tax expense | 526 | 880 | ||||||||||||||||||||||
| Net income | $ 2,122 | $ 2,143 | ||||||||||||||||||||||
| Earnings per share, basic (in dollars per share) | $ 7.70 | $ 7.08 | ||||||||||||||||||||||
| Earnings per share, diluted (in dollars per share) | $ 7.67 | $ 7.06 | ||||||||||||||||||||||
| ASU 2016-02 | Flight Equipment | ||||||||||||||||||||||||
| Operating property and equipment: | ||||||||||||||||||||||||
| Operating lease assets | 2,380 | 3,102 | $ 2,380 | $ 3,102 | ||||||||||||||||||||
| ASU 2016-02 | Other Property and Equipment | ||||||||||||||||||||||||
| Operating property and equipment: | ||||||||||||||||||||||||
| Operating lease assets | 2,882 | 2,975 | 2,882 | 2,975 | ||||||||||||||||||||
| ASU 2016-02 | New Lease Standard Adjustments | ||||||||||||||||||||||||
| Current assets: | ||||||||||||||||||||||||
| Receivables, less allowance for doubtful accounts (2018—$8; 2017—$7) | 80 | 126 | 80 | 126 | ||||||||||||||||||||
| Prepaid expenses and other | (180) | (208) | (180) | (208) | ||||||||||||||||||||
| Operating property and equipment: | ||||||||||||||||||||||||
| Other property and equipment | (1,041) | (922) | (1,041) | (922) | ||||||||||||||||||||
| Less-Accumulated depreciation and amortization (owned) | 140 | 92 | 140 | 92 | ||||||||||||||||||||
| Flight equipment (Finance leases) | (37) | (211) | (37) | (211) | ||||||||||||||||||||
| Less-Accumulated amortization | 8 | 169 | 8 | 169 | ||||||||||||||||||||
| Current liabilities: | ||||||||||||||||||||||||
| Current maturities of finance leases | (26) | (50) | (26) | (50) | ||||||||||||||||||||
| Current maturities of operating leases | 719 | 949 | 719 | 949 | ||||||||||||||||||||
| Other | (66) | (58) | (66) | (58) | ||||||||||||||||||||
| Long-term obligations under finance leases | (910) | (766) | (910) | (766) | ||||||||||||||||||||
| Long-term obligations under operating leases | 5,276 | 5,789 | 5,276 | 5,789 | ||||||||||||||||||||
| Other liabilities and deferred credits: | ||||||||||||||||||||||||
| Deferred income taxes | 14 | 16 | 14 | 16 | ||||||||||||||||||||
| Other | (822) | (811) | (822) | (811) | ||||||||||||||||||||
| Stockholders' equity: | ||||||||||||||||||||||||
| Retained earnings | 47 | 54 | 47 | 54 | ||||||||||||||||||||
| Operating expense: | ||||||||||||||||||||||||
| Regional capacity purchase | 48 | 36 | ||||||||||||||||||||||
| Landing fees and other rent | 90 | 70 | ||||||||||||||||||||||
| Depreciation and amortization | (75) | (53) | ||||||||||||||||||||||
| Operating expenses | 63 | 53 | ||||||||||||||||||||||
| Operating income | (63) | (53) | ||||||||||||||||||||||
| Nonoperating income (expense): | ||||||||||||||||||||||||
| Interest expense | 59 | 45 | ||||||||||||||||||||||
| Interest capitalized | (5) | (10) | ||||||||||||||||||||||
| Total nonoperating expense, net | 53 | 36 | ||||||||||||||||||||||
| Income before income taxes | (10) | (17) | ||||||||||||||||||||||
| Income tax expense | (3) | (16) | ||||||||||||||||||||||
| Net income | $ (7) | $ (1) | ||||||||||||||||||||||
| Earnings per share, basic (in dollars per share) | $ (0.03) | $ 0.00 | ||||||||||||||||||||||
| Earnings per share, diluted (in dollars per share) | $ (0.03) | $ 0.00 | ||||||||||||||||||||||
| ASU 2016-02 | New Lease Standard Adjustments | Flight Equipment | ||||||||||||||||||||||||
| Operating property and equipment: | ||||||||||||||||||||||||
| Operating lease assets | 2,380 | 3,102 | $ 2,380 | $ 3,102 | ||||||||||||||||||||
| ASU 2016-02 | New Lease Standard Adjustments | Other Property and Equipment | ||||||||||||||||||||||||
| Operating property and equipment: | ||||||||||||||||||||||||
| Operating lease assets | $ 2,882 | $ 2,975 | $ 2,882 | $ 2,975 | ||||||||||||||||||||
| ||||||||||||||||||||||||
| X | ||||||||||
- Definition Finance Leases, Lessee, Balance Sheet Assets By Major Class, Accumulated Depreciation No definition available.
|
| X | ||||||||||
- Definition Finance Leases, Lessee, Balance Sheet Assets By Major Class, Flight Equipment, Gross No definition available.
|
| X | ||||||||||
- Definition Amount of liabilities incurred to vendors for goods and services received, and accrued liabilities classified as other, payable within one year or the normal operating cycle, if longer. No definition available.
|
| X | ||||||||||
- Definition Costs incurred related to air services provided by third-party transportation companies, including regional affiliates. No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of capital lease obligation due within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Gross amount of long-lived, depreciable flight assets used in the entity's principle business operations, subject to a lease and meeting the criteria for capitalization. No definition available.
|
| X | ||||||||||
- Definition Total costs of sales and operating expenses for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as current. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Present value of lessee's discounted obligation for lease payments from finance lease, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of interest costs capitalized disclosed as an adjusting item to interest costs incurred. No definition available.
|
| X | ||||||||||
- Definition Amount of the cost of borrowed funds accounted for as interest expense. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Direct costs incurred at airports in which the entity conducts flight operations. The costs primarily consist of fees paid to the airport authority for takeoff and landing, gate space and facilities, allocations of common space such as security and other terminal costs and fuel storage facilities. No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition The net result for the period of deducting operating expenses from operating revenues. No definition available.
|
| X | ||||||||||
- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as current. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of lessee's right to use underlying asset under operating lease. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are expected to be paid after one year (or the normal operating cycle, if longer), from the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount before accumulated depreciation, depletion and amortization of other physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The cumulative amount of depreciation (related to long-lived, depreciable flight assets owned by the entity and used in the entity's principle business operations and capitalized assets classified as property, plant and equipment that are owned by the entity) that has been recognized in the income statement. No definition available.
|
| X | ||||||||||
- Definition The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The cumulative amount of the reporting entity's undistributed earnings or deficit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
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| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
Goodwill and Other Intangible Assets - Information about Goodwill and Other Intangible Assets (Details) - USD ($) $ in Millions |
Dec. 31, 2018 |
Dec. 31, 2017 |
|||
|---|---|---|---|---|---|
| Goodwill and Intangible Assets Disclosure [Abstract] | |||||
| Goodwill | $ 4,523 | $ 4,523 | [1] | ||
| Finite-Lived Intangible Assets [Line Items] | |||||
| Gross carrying amount | 1,756 | 1,757 | |||
| Accumulated amortization | 1,380 | 1,313 | [1] | ||
| Indefinite-lived Intangible Assets [Line Items] | |||||
| Gross carrying amount | 2,783 | 3,095 | |||
| Route authorities | |||||
| Indefinite-lived Intangible Assets [Line Items] | |||||
| Gross carrying amount | 1,240 | 1,562 | |||
| Airport slots and gates | |||||
| Indefinite-lived Intangible Assets [Line Items] | |||||
| Gross carrying amount | 546 | 536 | |||
| Tradenames and logos | |||||
| Indefinite-lived Intangible Assets [Line Items] | |||||
| Gross carrying amount | 593 | 593 | |||
| Alliances | |||||
| Indefinite-lived Intangible Assets [Line Items] | |||||
| Gross carrying amount | 404 | 404 | |||
| Frequent flyer database | |||||
| Finite-Lived Intangible Assets [Line Items] | |||||
| Gross carrying amount | 1,177 | 1,177 | |||
| Accumulated amortization | 884 | 832 | |||
| Hubs | |||||
| Finite-Lived Intangible Assets [Line Items] | |||||
| Gross carrying amount | 145 | 145 | |||
| Accumulated amortization | 97 | 89 | |||
| Contracts | |||||
| Finite-Lived Intangible Assets [Line Items] | |||||
| Gross carrying amount | 120 | 121 | |||
| Accumulated amortization | 106 | 103 | |||
| Patents and tradenames | |||||
| Finite-Lived Intangible Assets [Line Items] | |||||
| Gross carrying amount | 108 | 108 | |||
| Accumulated amortization | 108 | 108 | |||
| Airport slots and gates | |||||
| Finite-Lived Intangible Assets [Line Items] | |||||
| Gross carrying amount | 97 | 97 | |||
| Accumulated amortization | 97 | 97 | |||
| Other | |||||
| Finite-Lived Intangible Assets [Line Items] | |||||
| Gross carrying amount | 109 | 109 | |||
| Accumulated amortization | $ 88 | $ 84 | |||
| |||||
| X | ||||||||||
- Definition Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
Goodwill and Other Intangible Assets - Narrative (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Goodwill and Intangible Assets Disclosure [Abstract] | |||
| Amortization expense | $ 67 | $ 79 | $ 90 |
| Projected amortization expense: | |||
| Projected amortization expense in 2019 | 61 | ||
| Projected amortization expense in 2020 | 55 | ||
| Projected amortization expense in 2021 | 50 | ||
| Projected amortization expense in 2022 | 40 | ||
| Projected amortization expense in 2023 | $ 37 | ||
| X | ||||||||||
- Definition The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- References No definition available.
|
Common Stockholders' Equity and Preferred Securities (Details) - USD ($) |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Equity [Abstract] | |||
| Number of shares repurchased (in shares) | 17,500,000 | ||
| Repurchases of common stock | $ 1,250,000,000 | $ 1,844,000,000 | $ 2,607,000,000 |
| Share repurchase program additional amount authorized | $ 3,000,000,000.0 | ||
| Amount remaining under repurchase programs | $ 1,800,000,000 | ||
| Common stock reserved for future issuance (in shares) | 10,000,000 | ||
| Junior preferred stock outstanding (in shares) | 2 | ||
| Junior preferred stock par value per share (in dollars per share) | $ 0.01 | ||
| Preferred stock authorized to issue (in shares) | 250,000,000 | ||
| X | ||||||||||
- Definition Aggregate number of common shares reserved for future issuance. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of stock repurchase plan authorized. No definition available.
|
| X | ||||||||||
- Definition Amount remaining of a stock repurchase plan authorized. No definition available.
|
| X | ||||||||||
- Definition Number of shares that have been repurchased during the period and are being held in treasury. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|||||
| Earnings Per Share [Abstract] | |||||||||||||||
| Earnings available to common stockholders | $ 2,129 | $ 2,144 | $ 2,234 | ||||||||||||
| Basic weighted-average shares outstanding (in shares) | 275.5 | 302.7 | 329.9 | ||||||||||||
| Effect of employee stock awards (in shares) | 1.2 | 0.9 | 0.4 | ||||||||||||
| Diluted weighted-average shares outstanding (in shares) | 276.7 | 303.6 | 330.3 | ||||||||||||
| Earnings per share, basic (in dollars per share) | $ 1.71 | $ 3.07 | $ 2.49 | $ 0.52 | $ 1.99 | $ 2.15 | $ 2.67 | $ 0.32 | $ 7.73 | $ 7.08 | [1] | $ 6.77 | [1] | ||
| Earnings per share, diluted (in dollars per share) | $ 1.70 | $ 3.06 | $ 2.48 | $ 0.52 | $ 1.98 | $ 2.15 | $ 2.67 | $ 0.32 | $ 7.70 | $ 7.06 | [1] | $ 6.76 | [1] | ||
| |||||||||||||||
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
Share-Based Compensation Plans - Narrative (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Fair value of RSUs and restricted stock vested in period | $ 70.0 | $ 76.0 | $ 80.0 |
| Stock option awards outstanding (in shares) | 400 | ||
| Stock option awards exercisable (in shares) | 200 | ||
| Weighted-average exercise price of stock options outstanding (in dollars per share) | $ 55.62 | ||
| Weighted-average exercise price of stock options exercisable (in dollars per share) | $ 47.07 | ||
| Intrinsic value of stock options outstanding | $ 12.0 | ||
| Intrinsic value of stock options exercisable | $ 6.0 | ||
| Weighted average remaining contractual lives of stock options outstanding | 5 years 9 months 18 days | ||
| Weighted average remaining contractual lives of stock options exercisable | 3 years 9 months 18 days | ||
| RSUs | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Awards granted (in shares) | 1,800 | ||
| Liabilities related to share based payments | $ 51.0 | ||
| Payment related to share-based liabilities | $ 28.0 | $ 50.0 | $ 69.0 |
| Time-Vested RSUs | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Awards granted (in shares) | 1,100 | ||
| Vesting period | 3 years | ||
| Number of days used to compute performance period average closing price of restricted stock units | 20 days | ||
| Performance-Based RSUs | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Awards granted (in shares) | 700 | ||
| Vesting period | 3 years | ||
| Number of days used to compute performance period average closing price of restricted stock units | 20 days | ||
| Stock Options | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Stock options granted (in shares) | 36 | 100 | |
| Weighted-average grant date exercise price of stock options granted (in dollars per share) | $ 77.56 | ||
| Weighted-average grant date fair value of stock options granted | $ 0.7 | ||
| Stock Options | Exercise Prices at a 25% Premium of the Grant Date Fair Value | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Stock options granted (in shares) | 300 | ||
| Weighted-average grant date exercise price of stock options granted (in dollars per share) | $ 56.19 | ||
| Weighted-average grant date fair value of stock options granted | $ 2.3 | ||
| Percentage of premium of the grant date fair market value | 25.00% | ||
| X | ||||||||||
- Definition The time period over which the stock closing prices are averaged to arrive at a per-share valuation for equity based awards such as Restricted Stock Units, Performance Share and other equity based awards. No definition available.
|
| X | ||||||||||
- Definition Percentage of Premium on Grant Date Fair Market Value No definition available.
|
| X | ||||||||||
- Definition Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements. No definition available.
|
| X | ||||||||||
- Definition Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Gross number of share options (or share units) granted during the period. No definition available.
|
| X | ||||||||||
- Definition Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Number of options outstanding, including both vested and non-vested options. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. No definition available.
|
| X | ||||||||||
- Definition Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Gross value of stock (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Stock issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans. No definition available.
|
| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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Share-Based Compensation Plans - Information Related to Share-Based Compensation Plan Cost (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Compensation cost | $ 101 | $ 73 | $ 70 |
| RSUs | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Compensation cost | 98 | 63 | 58 |
| Restricted stock | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Compensation cost | 2 | 8 | 11 |
| Stock options | |||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||
| Compensation cost | $ 1 | $ 2 | $ 1 |
| X | ||||||||||
- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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Share-Based Compensation Plans - Summary of Unearned Compensation and Weighted-Average Remaining Period to Recognize Costs (Details) $ in Millions |
12 Months Ended |
|---|---|
|
Dec. 31, 2018
USD ($)
| |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Unearned compensation | $ 68 |
| RSUs | |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Unearned compensation | $ 66 |
| Weighted average remaining period | 1 year 7 months 6 days |
| Stock options | |
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |
| Unearned compensation | $ 2 |
| Weighted average remaining period | 2 years 7 months 6 days |
| X | ||||||||||
- Definition Unrecognized cost of unvested share-based compensation awards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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Share-Based Compensation Plans - Summary of RSU and Restricted Stock Activity (Details) - $ / shares shares in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Equity Awards - RSUs | |||
| Awards | |||
| Outstanding (in shares) | 1.4 | 0.8 | 0.0 |
| Granted (in shares) | 1.1 | 1.0 | 0.9 |
| Vested (in shares) | (0.5) | (0.3) | 0.0 |
| Forfeited (in shares) | (0.2) | (0.1) | (0.1) |
| Outstanding (in shares) | 1.8 | 1.4 | 0.8 |
| Weighted- Average Grant Price | |||
| Outstanding (in dollars per share) | $ 63.99 | $ 51.67 | $ 0.00 |
| Granted (in dollars per share) | 67.74 | 71.68 | 51.60 |
| Vested (in dollars per share) | 63.02 | 51.81 | 0.00 |
| Forfeited (in dollars per share) | 67.34 | 57.49 | 50.57 |
| Outstanding (in dollars per share) | $ 66.29 | $ 63.99 | $ 51.67 |
| Liability Awards - RSUs | |||
| Awards | |||
| Outstanding (in shares) | 1.8 | 2.1 | 2.6 |
| Granted (in shares) | 0.7 | 0.6 | 1.0 |
| Vested (in shares) | (0.5) | (0.7) | (1.4) |
| Forfeited (in shares) | (0.1) | (0.2) | (0.1) |
| Outstanding (in shares) | 1.9 | 1.8 | 2.1 |
| Restricted Stock | |||
| Awards | |||
| Outstanding (in shares) | 0.3 | 0.5 | 0.3 |
| Granted (in shares) | 0.0 | 0.0 | 0.4 |
| Vested (in shares) | (0.2) | (0.2) | (0.1) |
| Forfeited (in shares) | 0.0 | 0.0 | (0.1) |
| Outstanding (in shares) | 0.1 | 0.3 | 0.5 |
| Weighted- Average Grant Price | |||
| Outstanding (in dollars per share) | $ 52.30 | $ 52.00 | $ 48.68 |
| Granted (in dollars per share) | 0.00 | 0.00 | 50.63 |
| Vested (in dollars per share) | 53.24 | 51.60 | 41.47 |
| Forfeited (in dollars per share) | 0.00 | 0.00 | 53.42 |
| Outstanding (in dollars per share) | $ 51.17 | $ 52.30 | $ 52.00 |
| X | ||||||||||
- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
|
| X | ||||||||||
- Definition The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
|
| X | ||||||||||
- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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Accumulated Other Comprehensive Income (Loss) - Components of the Company's AOCI (Details) - USD ($) $ in Millions |
12 Months Ended | ||||||
|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|||||
| AOCI Attributable to Parent, Net of Tax [Roll Forward] | |||||||
| Balance, deferred taxes | $ (39) | $ 26 | $ (256) | ||||
| Balance | 8,734 | [1] | 8,574 | 8,966 | |||
| Other comprehensive income (loss) before reclassifications, deferred taxes | (83) | 74 | 187 | ||||
| Other comprehensive income (loss) before reclassifications, net of tax | 289 | (239) | (334) | ||||
| Amounts reclassified from accumulated other comprehensive income, deferred taxes | (13) | (21) | 95 | ||||
| Amounts reclassified from accumulated other comprehensive income, net of tax | 49 | 39 | 336 | ||||
| Reclassification of stranded tax effects, tax | (118) | ||||||
| Amounts reclassified to retained earnings, deferred taxes | (1) | ||||||
| Amounts reclassified to retained earnings, net of taxes | 6 | ||||||
| Balance, deferred taxes | (136) | (39) | 26 | ||||
| Balance | 9,995 | 8,734 | [1] | 8,574 | |||
| Decrease (increase) in prior service credits | 3 | 0 | (30) | ||||
| Decrease (increase) in actuarial losses | 380 | 306 | 560 | ||||
| Accumulated Other Comprehensive Income (Loss) | |||||||
| AOCI Attributable to Parent, Net of Tax [Roll Forward] | |||||||
| Balance | (1,147) | (829) | (831) | ||||
| Reclassification of stranded tax effects | (118) | ||||||
| Balance | (803) | (1,147) | (829) | ||||
| Pension and Other Postretirement Liabilities | |||||||
| AOCI Attributable to Parent, Net of Tax [Roll Forward] | |||||||
| Balance, before tax | (1,102) | (854) | (363) | ||||
| Other comprehensive income (loss) before reclassifications, before tax | 377 | (306) | (517) | ||||
| Amounts reclassified from accumulated other comprehensive income, before tax | 62 | 58 | 26 | ||||
| Amounts reclassified to retained earnings, before tax | 0 | ||||||
| Balance, before tax | (663) | (1,102) | (854) | ||||
| Fuel Derivatives Contracts | |||||||
| AOCI Attributable to Parent, Net of Tax [Roll Forward] | |||||||
| Balance, before tax | 0 | (2) | (215) | ||||
| Other comprehensive income (loss) before reclassifications, before tax | 0 | 0 | (4) | ||||
| Amounts reclassified from accumulated other comprehensive income, before tax | 0 | 2 | 217 | ||||
| Amounts reclassified to retained earnings, before tax | 0 | ||||||
| Balance, before tax | 0 | 0 | (2) | ||||
| Investments and Other | |||||||
| AOCI Attributable to Parent, Net of Tax [Roll Forward] | |||||||
| Balance, before tax | (6) | 1 | 3 | ||||
| Other comprehensive income (loss) before reclassifications, before tax | (5) | (7) | 0 | ||||
| Amounts reclassified from accumulated other comprehensive income, before tax | 0 | 0 | (2) | ||||
| Amounts reclassified to retained earnings, before tax | 7 | ||||||
| Balance, before tax | $ (4) | $ (6) | $ 1 | ||||
| |||||||
| X | ||||||||||
- Definition Reclassification From Accumulated Other Comprehensive Income To Retained Earnings. Current Period, Tax No definition available.
|
| X | ||||||||||
- Definition Reclassification From Accumulated Other Comprehensive Income, To Retained Earnings Current Period, before Tax No definition available.
|
| X | ||||||||||
- Definition Reclassification from accumulated other comprehensive income, to retained earnings current period, net of tax. No definition available.
|
| X | ||||||||||
- Definition Tax Cuts and Jobs Act of 2017, Reclassification from AOCI to Retained Earnings, Tax Effect No definition available.
|
| X | ||||||||||
- Definition Tax Cuts And Jobs Act Of 2017 Reclassification From Aoci, Tax No definition available.
|
| X | ||||||||||
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
|
| X | ||||||||||
- Definition Amount before tax of increase (decrease) in accumulated equity from transactions and other events and circumstances from non-owner sources, attributable to parent. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners). No definition available.
|
| X | ||||||||||
- Definition Amount of tax expense (benefit) allocated to accumulated other comprehensive income (loss) attributable to parent. No definition available.
|
| X | ||||||||||
- Definition Amount, after tax, of cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount, after tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount before tax and reclassification adjustments of other comprehensive income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount after tax, before reclassification adjustments of other comprehensive income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of tax expense (benefit) allocated to other comprehensive income (loss) before reclassification adjustment from accumulated other comprehensive income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount before tax of reclassification adjustments of other comprehensive income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount after tax of reclassification adjustments of other comprehensive income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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| X | ||||||||||
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| X | ||||||||||
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| X | ||||||||||
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Accumulated Other Comprehensive Income (Loss) - Details about AOCI Components (Details) - USD ($) $ in Millions |
12 Months Ended | ||||||
|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|||||
| Accumulated Other Comprehensive Income (Loss) [Line Items] | |||||||
| Aircraft fuel | $ 9,307 | $ 6,913 | [1] | $ 5,813 | [1] | ||
| Miscellaneous, net | 76 | 101 | [1] | 11 | [1] | ||
| Fuel derivative contracts | Amount Reclassified from AOCI to Income | |||||||
| Accumulated Other Comprehensive Income (Loss) [Line Items] | |||||||
| Aircraft fuel | 0 | 2 | 217 | ||||
| Pension and Postretirement liabilities and other | Amount Reclassified from AOCI to Income | |||||||
| Accumulated Other Comprehensive Income (Loss) [Line Items] | |||||||
| Miscellaneous, net | 62 | 58 | 26 | ||||
| Investments and other | Amount Reclassified from AOCI to Income | |||||||
| Accumulated Other Comprehensive Income (Loss) [Line Items] | |||||||
| Miscellaneous, net | $ 0 | $ 0 | $ (2) | ||||
| |||||||
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Fuel costs incurred that are directly related to goods produced and sold and services rendered during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of income (expense) related to nonoperating activities, classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
|
Income Taxes - Narrative (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Income Taxes [Line Items] | |||
| Federal statutory income tax rate | 21.00% | ||
| Income tax benefit for the one-time transition tax | $ 4 | ||
| Unrecognized tax benefits | 39 | $ 21 | $ 74 |
| Unrecognized tax benefits that would impact effective tax rate if recognized | 39 | ||
| 2030 | |||
| Income Taxes [Line Items] | |||
| NOL carry forwards | 600 | ||
| Thereafter | |||
| Income Taxes [Line Items] | |||
| NOL carry forwards | 1,000 | ||
| Federal | |||
| Income Taxes [Line Items] | |||
| NOL carry forwards | 1,600 | ||
| State | |||
| Income Taxes [Line Items] | |||
| NOL carry forwards | 83 | ||
| NOL carry forwards, valuation allowance | $ 48 |
| X | ||||||||||
- Definition Effective Income Tax Rate Reconciliation, Tax Cuts And Jobs Act Of 2017, Transition Tax On Accumulated Foreign Earnings, Amount No definition available.
|
| X | ||||||||||
- Definition Income Taxes [Line Items] No definition available.
|
| X | ||||||||||
- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
|
Income Taxes - Income Tax Provision (Benefit) Differed from Amounts Computed at the Statutory Federal Income Tax Rate and Significant Components (Details) - USD ($) $ in Millions |
12 Months Ended | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Sep. 30, 2015 |
|||||||||||
| Income Taxes [Line Items] | ||||||||||||||
| Income tax provision at statutory rate | $ 558 | $ 1,064 | $ 1,320 | |||||||||||
| State income taxes, net of federal income tax benefit | 29 | 30 | 38 | |||||||||||
| Foreign tax rate differential | (84) | (43) | 0 | |||||||||||
| Global intangible low-taxed income | 4 | 0 | 0 | |||||||||||
| Foreign income taxes | 2 | 3 | 3 | |||||||||||
| Nondeductible employee meals | 12 | 17 | 16 | |||||||||||
| Impact of Tax Act | (5) | (179) | 0 | |||||||||||
| Income tax adjustment from AOCI | 0 | 0 | 180 | |||||||||||
| State rate change | 3 | 12 | (12) | |||||||||||
| Valuation allowance | (3) | (16) | 20 | |||||||||||
| Other, net | 13 | 8 | (26) | |||||||||||
| Income tax expense (benefit) | 529 | 896 | [1] | 1,539 | [1] | |||||||||
| Current | 14 | (77) | (92) | |||||||||||
| Deferred | 515 | 973 | [2] | 1,631 | [2] | |||||||||
| Valuation allowance recorded | 59 | 63 | ||||||||||||
| AOCI | ||||||||||||||
| Income Taxes [Line Items] | ||||||||||||||
| Income tax adjustment from AOCI | 180 | |||||||||||||
| Valuation allowance recorded | $ 465 | |||||||||||||
| AOCI | Pension and Other Postretirement Liabilities | ||||||||||||||
| Income Taxes [Line Items] | ||||||||||||||
| Valuation allowance recorded | 285 | |||||||||||||
| AOCI | Designated as Hedging Instrument | Fuel | ||||||||||||||
| Income Taxes [Line Items] | ||||||||||||||
| Valuation allowance recorded | $ 180 | |||||||||||||
| United Airlines, Inc. | ||||||||||||||
| Income Taxes [Line Items] | ||||||||||||||
| Income tax provision at statutory rate | 559 | 1,065 | 1,321 | |||||||||||
| State income taxes, net of federal income tax benefit | 29 | 30 | 38 | |||||||||||
| Foreign tax rate differential | (84) | (43) | 0 | |||||||||||
| Global intangible low-taxed income | 4 | 0 | 0 | |||||||||||
| Foreign income taxes | 2 | 3 | 3 | |||||||||||
| Nondeductible employee meals | 12 | 17 | 16 | |||||||||||
| Impact of Tax Act | (5) | (196) | 0 | |||||||||||
| Income tax adjustment from AOCI | 0 | 0 | 180 | |||||||||||
| State rate change | 3 | 12 | (12) | |||||||||||
| Valuation allowance | (3) | (16) | 20 | |||||||||||
| Other, net | 12 | 7 | (25) | |||||||||||
| Income tax expense (benefit) | 529 | 879 | [3] | 1,541 | [3] | |||||||||
| Current | 14 | (77) | (92) | |||||||||||
| Deferred | 515 | 956 | [4] | $ 1,633 | [4] | |||||||||
| Valuation allowance recorded | $ 59 | $ 63 | ||||||||||||
| ||||||||||||||
| X | ||||||||||
- Definition Effective Income Tax Rate Reconciliation, Foreign Income Taxes No definition available.
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| X | ||||||||||
- Definition Effective Income Tax Rate Reconciliation, Global Intangible Low-Taxed Income No definition available.
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| X | ||||||||||
- Definition Income tax adjustments from accumulated other comprehensive income. No definition available.
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| X | ||||||||||
- Definition Income tax rate reconciliation, impact of tax cuts and jobs act amount. No definition available.
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| X | ||||||||||
- Definition Income Taxes [Line Items] No definition available.
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| X | ||||||||||
- Definition Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to foreign income tax expense (benefit). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to nondeductible meals and entertainment expense. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to other adjustments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to state and local income tax expense (benefit). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
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Income Taxes - Temporary Differences and Carryforwards Giving Rise to Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions |
Dec. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Deferred income tax asset (liability): | ||
| Federal and state net operating loss (NOL) carryforwards | $ 398 | $ 601 |
| Deferred revenue | 1,232 | 1,090 |
| Employee benefits, including pension, postretirement and medical | 885 | 1,051 |
| Other | 408 | 351 |
| Less: Valuation allowance | (59) | (63) |
| Total deferred tax assets | 2,864 | 3,030 |
| Depreciation | (2,929) | (2,431) |
| Intangibles | (749) | (803) |
| Total deferred tax liabilities | (3,678) | (3,234) |
| Net deferred tax liability | (814) | (204) |
| United Airlines, Inc. | ||
| Deferred income tax asset (liability): | ||
| Federal and state net operating loss (NOL) carryforwards | 372 | 574 |
| Deferred revenue | 1,232 | 1,090 |
| Employee benefits, including pension, postretirement and medical | 885 | 1,051 |
| Other | 406 | 351 |
| Less: Valuation allowance | (59) | (63) |
| Total deferred tax assets | 2,836 | 3,003 |
| Depreciation | (2,929) | (2,431) |
| Intangibles | (749) | (803) |
| Total deferred tax liabilities | (3,678) | (3,234) |
| Net deferred tax liability | $ (842) | $ (231) |
| X | ||||||||||
- Definition Amount of deferred tax liability attributable to taxable temporary differences. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred income. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensation and benefits costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences without jurisdictional netting. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Details
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Pension and Other Postretirement Plans - Reconciliation of the Change in Benefit Obligation and Plan Asset, Funded Status and Amounts Recognized in the Financial Statements (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Pension Benefits | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Accumulated benefit obligation | $ 4,448 | $ 4,739 | |
| Change in projected benefit obligation: | |||
| Projected benefit obligation at beginning of year | 5,852 | $ 5,253 | |
| Service cost | 228 | 195 | 112 |
| Interest cost | 217 | 220 | 200 |
| Actuarial (gain) loss | (601) | 525 | |
| Gross benefits paid and settlements | (292) | (366) | |
| Other | (8) | 25 | |
| Projected benefit obligation at end of year | 5,396 | 5,852 | |
| Change in plan assets: | |||
| Fair value of plan assets at beginning of year | 3,932 | 3,355 | |
| Actual (loss) return on plan assets | (215) | 510 | |
| Employer contributions | 413 | 419 | |
| Gross benefits paid and settlements | (292) | (366) | |
| Other | (11) | 14 | |
| Fair value of plan assets at end of year | 3,827 | 3,932 | |
| Funded status—Net amount recognized | (1,569) | (1,920) | |
| Amounts recognized in the consolidated balance sheets consist of: | |||
| Noncurrent asset | 13 | 9 | |
| Current liability | (6) | (8) | |
| Noncurrent liability | (1,576) | (1,921) | |
| Total liability | (1,569) | (1,920) | |
| Amounts recognized in accumulated other comprehensive loss consist of: | |||
| Net actuarial loss | (1,382) | (1,610) | |
| Prior service cost | (5) | (1) | |
| Total accumulated other comprehensive loss | (1,387) | (1,611) | |
| Other Postretirement Benefits | |||
| Change in projected benefit obligation: | |||
| Projected benefit obligation at beginning of year | 1,710 | 1,687 | |
| Service cost | 12 | 13 | 19 |
| Interest cost | 61 | 66 | 86 |
| Plan participants' contributions | 68 | 68 | |
| Actuarial (gain) loss | (285) | 40 | |
| Benefits paid | (181) | (178) | |
| Other | 6 | 14 | |
| Projected benefit obligation at end of year | 1,391 | 1,710 | |
| Change in plan assets: | |||
| Fair value of plan assets at beginning of year | 54 | $ 55 | |
| Actual (loss) return on plan assets | 1 | 1 | |
| Employer contributions | 111 | 108 | |
| Plan participants' contributions | 68 | 68 | |
| Benefits paid | (181) | (178) | |
| Fair value of plan assets at end of year | 53 | 54 | |
| Funded status—Net amount recognized | (1,338) | (1,656) | |
| Amounts recognized in the consolidated balance sheets consist of: | |||
| Current liability | (43) | (54) | |
| Noncurrent liability | (1,295) | (1,602) | |
| Total liability | (1,338) | (1,656) | |
| Amounts recognized in accumulated other comprehensive loss consist of: | |||
| Net actuarial loss | 554 | 301 | |
| Prior service cost | 170 | 208 | |
| Total accumulated other comprehensive loss | $ 724 | $ 509 | |
| X | ||||||||||
- Definition Defined Benefit Plan Benefits Paid And Settlements No definition available.
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| X | ||||||||||
- Definition Defined benefit plan other changes plan assets No definition available.
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| X | ||||||||||
- Definition Defined Benefit Plan, Plan Assets, Benefits Paid And Payments For Settlement No definition available.
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| X | ||||||||||
- Definition Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount, before tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount, before tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of contributions received by defined benefit plan from participant which increase benefit obligation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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| X | ||||||||||
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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| X | ||||||||||
- Definition Amount of contribution received by defined benefit plan from employer which increases plan assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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| X | ||||||||||
- Definition Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of increase (decrease) in benefit obligation of defined benefit plan from change, classified as other. No definition available.
|
| X | ||||||||||
- Definition Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of contributions received by defined benefit plan from participant which increases plan assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as current. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Details
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| X | ||||||||||
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Pension and Other Postretirement Plans - Accumulated Benefit Obligation and Projected Benefit Obligation in Excess of Plan Assets (Details) - USD ($) $ in Millions |
Dec. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Retirement Benefits [Abstract] | ||
| Projected benefit obligation | $ 5,196 | $ 5,637 |
| Accumulated benefit obligation | 4,286 | 4,567 |
| Fair value of plan assets | $ 3,614 | $ 3,709 |
| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Amount of accumulated benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Fair value of plan assets for defined benefit pension plan with accumulated benefit obligation in excess of plan assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Pension and Other Postretirement Plans - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |||
| Curtailment gain | $ 0 | $ 0 | $ (107) |
| Pension Benefits | |||
| Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |||
| Service cost | 228 | 195 | 112 |
| Interest cost | 217 | 220 | 200 |
| Expected return on plan assets | (292) | (243) | (216) |
| Curtailment gain | 0 | 0 | 0 |
| Amortization of unrecognized actuarial (gain) loss | 130 | 128 | 76 |
| Amortization of prior service credits | 0 | 0 | 0 |
| Other | 1 | 5 | 5 |
| Net periodic benefit cost (credit) | 284 | 305 | 177 |
| Other Postretirement Benefits | |||
| Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] | |||
| Service cost | 12 | 13 | 19 |
| Interest cost | 61 | 66 | 86 |
| Expected return on plan assets | (2) | (2) | (2) |
| Curtailment gain | 0 | 0 | (107) |
| Amortization of unrecognized actuarial (gain) loss | (32) | (33) | (19) |
| Amortization of prior service credits | (37) | (37) | (31) |
| Other | 0 | 0 | 0 |
| Net periodic benefit cost (credit) | $ 2 | $ 7 | $ (54) |
| X | ||||||||||
- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of defined benefit plan cost (credit), classified as other. No definition available.
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| X | ||||||||||
- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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Pension and Other Postretirement Plans - Assumptions Used for Benefit Plans (Details) |
12 Months Ended | |
|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
|
| Pension Benefits | ||
| Assumptions used to determine benefit obligations | ||
| Discount rate | 4.20% | 3.65% |
| Rate of compensation increase | 3.89% | 3.89% |
| Assumptions used to determine net expense | ||
| Discount rate | 3.65% | 4.19% |
| Expected return on plan assets | 7.31% | 7.02% |
| Rate of compensation increase | 3.89% | 3.54% |
| Other Postretirement Benefits | ||
| Assumptions used to determine benefit obligations | ||
| Discount rate | 4.30% | 3.63% |
| Assumptions used to determine net expense | ||
| Discount rate | 3.63% | 4.07% |
| Expected return on plan assets | 3.00% | 3.00% |
| Health care cost trend rate assumed for next year | 6.00% | 6.25% |
| Rate to which the cost trend rate is assumed to decline (ultimate trend rate in 2023) | 5.00% | 5.00% |
| X | ||||||||||
- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Weighted average rate increase of compensation, used to determine benefit obligation of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine net periodic benefit cost of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Weighted average rate of compensation increase used to determine net periodic benefit cost of defined benefit plan. Plan includes, but is not limited to, pay-related defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Assumed rate, for next fiscal year, based on annual change in cost of health care cost benefits used to measure expected cost of benefits covered by defined benefit postretirement plan. Factors include, but are not limited to, estimate of health care inflation, change in health care utilization or delivery pattern, technological advances, and change in health status of participant. Excludes factors for change in composition of plan population by age and dependency status. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Ultimate trend rate for health care cost for defined benefit postretirement plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
|
Pension and Other Postretirement Plans - Allocation of Plan Assets (Details) - United Airlines, Inc. |
12 Months Ended |
|---|---|
Dec. 31, 2018 | |
| Equity securities | |
| Defined Benefit Plan Disclosure [Line Items] | |
| Expected long-term rate of return | 9.50% |
| Equity securities | Minimum | |
| Defined Benefit Plan Disclosure [Line Items] | |
| Percent of total | 30.00% |
| Equity securities | Maximum | |
| Defined Benefit Plan Disclosure [Line Items] | |
| Percent of total | 45.00% |
| Fixed-income securities | |
| Defined Benefit Plan Disclosure [Line Items] | |
| Expected long-term rate of return | 5.80% |
| Fixed-income securities | Minimum | |
| Defined Benefit Plan Disclosure [Line Items] | |
| Percent of total | 30.00% |
| Fixed-income securities | Maximum | |
| Defined Benefit Plan Disclosure [Line Items] | |
| Percent of total | 40.00% |
| Alternatives | |
| Defined Benefit Plan Disclosure [Line Items] | |
| Expected long-term rate of return | 7.30% |
| Alternatives | Minimum | |
| Defined Benefit Plan Disclosure [Line Items] | |
| Percent of total | 10.00% |
| Alternatives | Maximum | |
| Defined Benefit Plan Disclosure [Line Items] | |
| Percent of total | 25.00% |
| Other | |
| Defined Benefit Plan Disclosure [Line Items] | |
| Expected long-term rate of return | 7.80% |
| Other | Minimum | |
| Defined Benefit Plan Disclosure [Line Items] | |
| Percent of total | 0.00% |
| Other | Maximum | |
| Defined Benefit Plan Disclosure [Line Items] | |
| Percent of total | 10.00% |
| X | ||||||||||
- Definition Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Pension and Other Postretirement Plans - Narrative (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Defined Benefit Plan Disclosure [Line Items] | |||
| Effect on post retirement benefit obligation, 1% Decrease | $ 139 | ||
| Effect on total service and interest cost, 1% Decrease | 10 | ||
| Profit sharing and payroll tax expense | $ 334 | $ 349 | $ 628 |
| Minimum | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Percentage of pre-tax earnings paid for profit sharing plan | 5.00% | ||
| Maximum | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Percentage of pre-tax earnings paid for profit sharing plan | 20.00% | ||
| IAM National Pension Plan | Multi-Employer Pension Plans | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Multi-employer plan contributions | $ 435 | ||
| IAM National Pension Plan | Multi-Employer Pension Plans | Minimum | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Percent of company's contribution to plan | 5.00% | ||
| United Airlines, Inc. | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Expense for defined contribution plans | $ 693 | $ 656 | $ 592 |
| United Airlines, Inc. | Minimum | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Employer contribution percentage | 1.00% | ||
| United Airlines, Inc. | Maximum | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Employer contribution percentage | 16.00% | ||
| Pension Benefits | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Expected employer contributions to pension and postretirement plans | $ 318 | ||
| Other Postretirement Benefits | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Expected employer contributions to pension and postretirement plans | $ 95 | ||
| Other Postretirement Benefits | Deposit Administration Fund | |||
| Defined Benefit Plan Disclosure [Line Items] | |||
| Percent of plan assets invested | 100.00% | ||
| X | ||||||||||
- Definition Defined Benefit Plan Profit Sharing And Payroll Tax Expense No definition available.
|
| X | ||||||||||
- Definition Multiemployer Pension Employer Percentage No definition available.
|
| X | ||||||||||
- Definition Profit Sharing Plan, Percentage of Pre-Tax Earnings Paid No definition available.
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Amount of decrease in accumulated postretirement benefit obligation from one-percentage-point decrease in assumed health care cost trend rate. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of decrease in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point decrease in assumed health care cost trend rate. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. No definition available.
|
| X | ||||||||||
- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. No definition available.
|
| X | ||||||||||
- Definition Amount of contributions made to multiemployer plan by all employers who participate in plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Pension and Other Postretirement Plans - Pension and Other Postretirement Plan Assets (Details) - USD ($) $ in Millions |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|---|---|
| Level 3 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | $ 350 | $ 383 | $ 287 | |
| Pension Benefits | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 3,827 | 3,932 | $ 3,355 | |
| Pension Benefits | Level 1 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 478 | 301 | ||
| Pension Benefits | Level 2 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 751 | 1,091 | ||
| Pension Benefits | Level 3 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 297 | 329 | ||
| Pension Benefits | Assets Measured at NAV | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 2,301 | 2,211 | ||
| Pension Benefits | Equity securities funds | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 1,394 | 1,406 | ||
| Pension Benefits | Equity securities funds | Level 1 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 254 | 269 | ||
| Pension Benefits | Equity securities funds | Level 2 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 106 | 133 | ||
| Pension Benefits | Equity securities funds | Level 3 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 0 | 0 | ||
| Pension Benefits | Equity securities funds | Assets Measured at NAV | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 1,034 | 1,004 | ||
| Pension Benefits | Fixed-income securities | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 1,431 | 1,470 | ||
| Pension Benefits | Fixed-income securities | Level 1 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 0 | 0 | ||
| Pension Benefits | Fixed-income securities | Level 2 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 605 | 834 | ||
| Pension Benefits | Fixed-income securities | Level 3 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 21 | 18 | ||
| Pension Benefits | Fixed-income securities | Assets Measured at NAV | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 805 | 618 | ||
| Pension Benefits | Alternatives | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 596 | 637 | ||
| Pension Benefits | Alternatives | Level 1 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 0 | 0 | ||
| Pension Benefits | Alternatives | Level 2 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 0 | 0 | ||
| Pension Benefits | Alternatives | Level 3 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 134 | 139 | ||
| Pension Benefits | Alternatives | Assets Measured at NAV | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 462 | 498 | ||
| Pension Benefits | Other | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 406 | 419 | ||
| Pension Benefits | Other | Level 1 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 224 | 32 | ||
| Pension Benefits | Other | Level 2 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 40 | 124 | ||
| Pension Benefits | Other | Level 3 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 142 | 172 | ||
| Pension Benefits | Other | Assets Measured at NAV | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 0 | 91 | ||
| Other Postretirement Benefits | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 53 | 54 | $ 55 | |
| Other Postretirement Benefits | Deposit administration fund | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 53 | 54 | ||
| Other Postretirement Benefits | Deposit administration fund | Level 1 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 0 | 0 | ||
| Other Postretirement Benefits | Deposit administration fund | Level 2 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 0 | 0 | ||
| Other Postretirement Benefits | Deposit administration fund | Level 3 | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | 53 | 54 | ||
| Other Postretirement Benefits | Deposit administration fund | Assets Measured at NAV | ||||
| Defined Contribution Plan Disclosure [Line Items] | ||||
| Fair value of plan assets | $ 0 | $ 0 |
| X | ||||||||||
- Definition Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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Pension and Other Postretirement Plans - Defined Benefit Plan Assets Measured at Fair Value Using Unobservable Inputs (Details) - Level 3 - USD ($) $ in Millions |
12 Months Ended | |
|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
|
| Defined Benefit Plan, Change in Fair Value of Plan Assets, Level 3 Reconciliation [Roll Forward] | ||
| Fair value of plan assets at beginning of year | $ 383 | $ 287 |
| Actual return (loss) on plan assets: | ||
| Sold during the year | 10 | 7 |
| Held at year end | (21) | 16 |
| Purchases, sales, issuances and settlements (net) | (22) | 73 |
| Fair value of plan assets at end of year | $ 350 | $ 383 |
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets sold. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets still held. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
|
| X | ||||||||||
- Definition Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from purchases, sales and settlements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Details
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Pension and Other Postretirement Plans - Estimated Future Benefit Payments (Details) $ in Millions |
Dec. 31, 2018
USD ($)
|
|---|---|
| Other Postretirement— subsidy receipts | |
| 2019 | $ 5 |
| 2020 | 6 |
| 2021 | 6 |
| 2022 | 6 |
| 2023 | 7 |
| Years 2024-2028 | 38 |
| Pension Benefits | |
| Pension and Other Postretirement | |
| 2019 | 329 |
| 2020 | 327 |
| 2021 | 353 |
| 2022 | 367 |
| 2023 | 379 |
| Years 2024-2028 | 2,022 |
| Other Postretirement Benefits | |
| Pension and Other Postretirement | |
| 2019 | 100 |
| 2020 | 104 |
| 2021 | 108 |
| 2022 | 111 |
| 2023 | 113 |
| Years 2024-2028 | $ 575 |
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of prescription drug subsidy receipts expected after fifth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of prescription drug subsidy receipts expected in next fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of prescription drug subsidy receipts expected in fifth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of prescription drug subsidy receipts expected in fourth fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of prescription drug subsidy receipts expected in third fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of prescription drug subsidy receipts expected in second fiscal year following latest fiscal year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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Pension and Other Postretirement Plans - Participation in the IAM National Pension Plan (Details) - IAM National Pension Plan - Multi-Employer Pension Plans - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Multiemployer Plans [Line Items] | |||
| EIN | 516031295 | ||
| Pension Plan Number | 002 | ||
| Pension Protection Act Zone Status | Green | ||
| FIP/RP Status Pending/Implemented | No | ||
| Surcharge Imposed | No | ||
| United Airlines, Inc. | |||
| Multiemployer Plans [Line Items] | |||
| United's Contributions | $ 50 | $ 41 | $ 40 |
| X | ||||||||||
- Definition The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of contributions made to multiemployer plan by employer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Three digit plan number for a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Indicate the multiemployer plan's certified zone status as currently required by the Pension Protection Act of 2006 or a subsequent amendment thereof. The zone status categories are red (critical status), orange (seriously endangered), yellow (endangered), and green (none of the above). The acceptable values are "red", "orange", "yellow", "green", "other", and "NA". A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Indicate whether a funding improvement plan or rehabilitation plan has been implemented or is pending for a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. The acceptable values are "no", "pending", "implemented", "other", and "NA". Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Indicate whether the employer paid a surcharge to the pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. The acceptable values are "no", "yes", and "NA". Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Investments and Fair Value Measurements - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions |
12 Months Ended | ||||||||
|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
[1] | Dec. 31, 2016 |
[1] | Jan. 31, 2019 |
Nov. 29, 2018 |
|||
| Fair Value [Line Items] | |||||||||
| Investment in equity securities | $ 2,552.0 | $ 3,241.0 | $ 2,768.0 | ||||||
| Investments in securities accounted for under the equity method | $ 144.0 | ||||||||
| EETC | |||||||||
| Fair Value [Line Items] | |||||||||
| Available-for-sale securities remaining maturities | 2019 | ||||||||
| Asset-backed Securities | Minimum | |||||||||
| Fair Value [Line Items] | |||||||||
| Available-for-sale securities remaining maturities | 1 year | ||||||||
| Asset-backed Securities | Maximum | |||||||||
| Fair Value [Line Items] | |||||||||
| Available-for-sale securities remaining maturities | 16 years | ||||||||
| Corporate Debt | Minimum | |||||||||
| Fair Value [Line Items] | |||||||||
| Available-for-sale securities remaining maturities | 1 year | ||||||||
| Corporate Debt | Maximum | |||||||||
| Fair Value [Line Items] | |||||||||
| Available-for-sale securities remaining maturities | 3 years | ||||||||
| CDARS | Maximum | |||||||||
| Fair Value [Line Items] | |||||||||
| Available-for-sale securities remaining maturities | 1 year | ||||||||
| U.S. Government and Other Securities | Minimum | |||||||||
| Fair Value [Line Items] | |||||||||
| Available-for-sale securities remaining maturities | 1 year | ||||||||
| Azul | |||||||||
| Fair Value [Line Items] | |||||||||
| Investment in equity securities | $ 138.0 | ||||||||
| Equity stake | 2.00% | ||||||||
| Azul | Preferred Stock | |||||||||
| Fair Value [Line Items] | |||||||||
| Equity stake | 8.00% | ||||||||
| Republic | |||||||||
| Fair Value [Line Items] | |||||||||
| Ownership stake | 19.00% | ||||||||
| ManaAir | Subsequent Event | |||||||||
| Fair Value [Line Items] | |||||||||
| Ownership stake | 49.90% | ||||||||
| ExpressJet Airlines, Inc. | ManaAir | Subsequent Event | |||||||||
| Fair Value [Line Items] | |||||||||
| Ownership stake | 100.00% | ||||||||
| Champlain | |||||||||
| Fair Value [Line Items] | |||||||||
| Ownership stake | 40.00% | ||||||||
| Fulcrum | |||||||||
| Fair Value [Line Items] | |||||||||
| Equity Securities Without Readily Determinable Fair Value, Ownership Interest | 0.09 | ||||||||
| Carrying value of other investment | $ 48.0 | ||||||||
| Synergy | |||||||||
| Fair Value [Line Items] | |||||||||
| Loan amount | $ 456.0 | ||||||||
| Number of shares that may be put to United (in shares) | 516,000,000 | ||||||||
| Number of ADRs that may be put to United (in shares) | 64,500,000 | ||||||||
| Percentage of installment that may be paid in shares (up to) | 25.00% | ||||||||
| Annual interest rate | 3.00% | ||||||||
| Number of shares that may be purchased at United's option (up to) (in shares) | 77,400,000.0 | ||||||||
| Shares subject to increase in value agreement (in shares) | 438,600,000.0 | ||||||||
| Kingsland | |||||||||
| Fair Value [Line Items] | |||||||||
| Number of shares that may be put to United (in shares) | 144,800,000.0 | ||||||||
| Number of ADRs that may be put to United (in shares) | 18,100,000 | ||||||||
| Market price of common stock at fifth anniversary (in dollars per share) | $ 12 | ||||||||
| Aggregate maximum possible combined put payment and guarantee amount | $ 217.2 | ||||||||
| |||||||||
| X | ||||||||||
- Definition Available for Sale Investment Maturity Term No definition available.
|
| X | ||||||||||
- Definition Available for Sale Investment Maturity Year No definition available.
|
| X | ||||||||||
- Definition Equity Securities, Ownership Percentage No definition available.
|
| X | ||||||||||
- Definition Equity Securities Without Readily Determinable Fair Value, Amount No definition available.
|
| X | ||||||||||
- Definition Equity Securities Without Readily Determinable Fair Value, Ownership Interest No definition available.
|
| X | ||||||||||
- Definition Fair Value [Line Items] No definition available.
|
| X | ||||||||||
- Definition Loan Receivable, Stated Interest Rate No definition available.
|
| X | ||||||||||
- Definition Loans Receivable, Aggregate Maximum Payment And Guarantee Amount No definition available.
|
| X | ||||||||||
- Definition Loans Receivable, Agreement, Put Option, Deposit Receipts No definition available.
|
| X | ||||||||||
- Definition Loans Receivable, Agreement, Put Options No definition available.
|
| X | ||||||||||
- Definition Loans Receivable, Guarantee And Payout Share Price At Fifth Anniversary No definition available.
|
| X | ||||||||||
- Definition Loans Receivable, Number Of Options To Acquire Shares No definition available.
|
| X | ||||||||||
- Definition Loans Receivable, Percentage Of Installment That May Be Paid In Shares No definition available.
|
| X | ||||||||||
- Definition Loans Receivable, Principal Amount No definition available.
|
| X | ||||||||||
- Definition Loans Receivable, Shares Subject To Increase In Value Agreement No definition available.
|
| X | ||||||||||
- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The cash outflow associated with the purchase of all investments (debt, security, other) during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Investments and Fair Value Measurements - Fair Value of Financial Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Millions |
Dec. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Level 1 | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Enhanced equipment trust certificates (EETC) | $ 0 | $ 0 |
| Avianca Holdings S.A. (AVH) Derivative Assets | 0 | 0 |
| Level 1 | Corporate Debt | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 0 | 0 |
| Level 1 | Asset-backed Securities | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 0 | 0 |
| Level 1 | CDARS | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 0 | 0 |
| Level 1 | U.S. Government and Agency Notes | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 0 | 0 |
| Level 1 | Other Fixed Income Securities | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 0 | 0 |
| Level 1 | Other Investments Measured At NAV | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 0 | 0 |
| Level 2 | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Cash and cash equivalents | 0 | 0 |
| Restricted cash | 0 | 0 |
| Equity securities | 0 | 0 |
| Enhanced equipment trust certificates (EETC) | 0 | 0 |
| Avianca Holdings S.A. (AVH) Derivative Assets | 0 | 0 |
| Level 2 | Other Investments Measured At NAV | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 0 | 0 |
| Level 3 | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Cash and cash equivalents | 0 | 0 |
| Restricted cash | 0 | 0 |
| Equity securities | 0 | 0 |
| Level 3 | Corporate Debt | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 0 | 0 |
| Level 3 | Asset-backed Securities | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 0 | 0 |
| Level 3 | CDARS | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 0 | 0 |
| Level 3 | U.S. Government and Agency Notes | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 0 | 0 |
| Level 3 | Other Fixed Income Securities | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 0 | 0 |
| Level 3 | Other Investments Measured At NAV | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 0 | 0 |
| Fair Value, Measurements, Recurring | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Cash and cash equivalents | 1,694 | 1,482 |
| Restricted cash | 105 | 109 |
| Equity securities | 249 | 99 |
| Enhanced equipment trust certificates (EETC) | 18 | 22 |
| Avianca Holdings S.A. (AVH) Derivative Assets | 11 | 0 |
| Fair Value, Measurements, Recurring | Corporate Debt | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 1,023 | 958 |
| Fair Value, Measurements, Recurring | Asset-backed Securities | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 746 | 753 |
| Fair Value, Measurements, Recurring | CDARS | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 75 | 120 |
| Fair Value, Measurements, Recurring | U.S. Government and Agency Notes | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 108 | 113 |
| Fair Value, Measurements, Recurring | Other Fixed Income Securities | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 116 | 188 |
| Fair Value, Measurements, Recurring | Other Investments Measured At NAV | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 188 | 184 |
| Fair Value, Measurements, Recurring | Level 1 | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Cash and cash equivalents | 1,694 | 1,482 |
| Restricted cash | 105 | 109 |
| Equity securities | 249 | 99 |
| Fair Value, Measurements, Recurring | Level 2 | Corporate Debt | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 1,023 | 958 |
| Fair Value, Measurements, Recurring | Level 2 | Asset-backed Securities | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 746 | 753 |
| Fair Value, Measurements, Recurring | Level 2 | CDARS | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 75 | 120 |
| Fair Value, Measurements, Recurring | Level 2 | U.S. Government and Agency Notes | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 108 | 113 |
| Fair Value, Measurements, Recurring | Level 2 | Other Fixed Income Securities | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Short-term investments | 116 | 188 |
| Fair Value, Measurements, Recurring | Level 3 | ||
| Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
| Enhanced equipment trust certificates (EETC) | 18 | 22 |
| Avianca Holdings S.A. (AVH) Derivative Assets | $ 11 | $ 0 |
| X | ||||||||||
- Definition Equity securities, fair value No definition available.
|
| X | ||||||||||
- Definition Restricted Cash Fair Value Disclosure No definition available.
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| X | ||||||||||
- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. No definition available.
|
| X | ||||||||||
- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Investments and Fair Value Measurements - Carrying Amounts and Estimated Fair Values of Financial Instruments (Details) - USD ($) $ in Millions |
Dec. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Carrying Amount | ||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
| Long-term debt, carrying amount | $ 13,445 | $ 13,268 |
| Synergy Term Loan, carrying amount | 478 | 0 |
| Fair Value | ||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
| Long-term debt, fair value | 13,450 | 13,787 |
| Synergy Term Loan, fair value | 422 | 0 |
| Fair Value | Level 1 | ||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
| Long-term debt, fair value | 0 | 0 |
| Synergy Term Loan, fair value | 0 | 0 |
| Fair Value | Level 2 | ||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
| Long-term debt, fair value | 9,525 | 10,115 |
| Synergy Term Loan, fair value | 0 | 0 |
| Fair Value | Level 3 | ||
| Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] | ||
| Long-term debt, fair value | 3,925 | 3,672 |
| Synergy Term Loan, fair value | $ 422 | $ 0 |
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. No definition available.
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Debt - Summary of Long-Term Debt (Details) - USD ($) $ in Millions |
12 Months Ended | ||||||||
|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jan. 31, 2017 |
||||||
| Debt Instrument [Line Items] | |||||||||
| Less: current portion of long-term debt | $ (1,230) | $ (1,565) | [1] | ||||||
| Long-term debt, net | 12,215 | 11,703 | [1] | ||||||
| United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Less: current portion of long-term debt | (1,230) | (1,565) | [2] | ||||||
| Long-term debt, net | 12,215 | 11,703 | [2] | ||||||
| UAL and United | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Long term debt | 13,636 | 13,431 | |||||||
| Less: unamortized debt discount, premiums and debt issuance costs | (191) | (163) | |||||||
| Less: current portion of long-term debt | (1,230) | (1,565) | |||||||
| Long-term debt, net | $ 12,215 | 11,703 | |||||||
| 6.375% Senior Notes due 2018 | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Fixed interest rate | 6.375% | ||||||||
| 6% Senior Notes due 2020 | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Fixed interest rate | 6.00% | ||||||||
| 4.25% Senior Notes due 2022 | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Fixed interest rate | 4.25% | ||||||||
| 4.25% Senior Notes due 2022 | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Fixed interest rate | 4.25% | ||||||||
| 5% Senior Notes due 2024 | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Fixed interest rate | 5.00% | ||||||||
| 5% Senior Notes due 2024 | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Fixed interest rate | 5.00% | ||||||||
| Secured Debt | Notes payable, fixed interest rates of 0.0% to 9.52% (weighted average rate of 4.18% as of December 31, 2018), payable through 2030 | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Long term debt | $ 8,811 | 8,661 | |||||||
| Weighted average rate | 4.18% | ||||||||
| Maturity date | 2030 | ||||||||
| Secured Debt | Notes payable, fixed interest rates of 0.0% to 9.52% (weighted average rate of 4.18% as of December 31, 2018), payable through 2030 | Minimum | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Fixed interest rate | 0.00% | ||||||||
| Secured Debt | Notes payable, fixed interest rates of 0.0% to 9.52% (weighted average rate of 4.18% as of December 31, 2018), payable through 2030 | Maximum | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Fixed interest rate | 9.52% | ||||||||
| Secured Debt | Notes payable, floating interest rates of the London interbank offered rate (LIBOR) plus 1.05% to 1.75%, payable through 2030 | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Long term debt | $ 2,051 | 1,880 | |||||||
| Secured Debt | Notes payable, floating interest rates of the London interbank offered rate (LIBOR) plus 1.05% to 1.75%, payable through 2030 | Maximum | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Maturity date | 2030 | ||||||||
| Secured Debt | Notes payable, floating interest rates of the London interbank offered rate (LIBOR) plus 1.05% to 1.75%, payable through 2030 | LIBOR | Minimum | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Basis spread on variable rate | 1.05% | ||||||||
| Secured Debt | Notes payable, floating interest rates of the London interbank offered rate (LIBOR) plus 1.05% to 1.75%, payable through 2030 | LIBOR | Maximum | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Basis spread on variable rate | 1.75% | ||||||||
| Secured Debt | Term loan, LIBOR plus 1.75%, or alternative rate based on certain market rates plus 0.75%, due 2024 | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Long term debt | $ 1,474 | 1,489 | |||||||
| Maturity date | 2024 | ||||||||
| Secured Debt | Term loan, LIBOR plus 1.75%, or alternative rate based on certain market rates plus 0.75%, due 2024 | LIBOR | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Basis spread on variable rate | 1.75% | ||||||||
| Secured Debt | Term loan, LIBOR plus 1.75%, or alternative rate based on certain market rates plus 0.75%, due 2024 | Alternative Rate Based on Certain Market Interest Rates | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Basis spread on variable rate | 0.75% | ||||||||
| Unsecured Debt | 6.375% Senior Notes due 2018 | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Long term debt | $ 0 | 300 | |||||||
| Fixed interest rate | 6.375% | ||||||||
| Maturity date | 2018 | ||||||||
| Unsecured Debt | 6% Senior Notes due 2020 | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Long term debt | $ 300 | 300 | |||||||
| Fixed interest rate | 6.00% | ||||||||
| Maturity date | 2020 | ||||||||
| Unsecured Debt | 4.25% Senior Notes due 2022 | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Long term debt | $ 400 | 400 | |||||||
| Fixed interest rate | 4.25% | ||||||||
| Maturity date | 2022 | ||||||||
| Unsecured Debt | 5% Senior Notes due 2024 | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Long term debt | $ 300 | 300 | |||||||
| Fixed interest rate | 5.00% | ||||||||
| Maturity date | 2024 | ||||||||
| Unsecured Debt | Other | United Airlines, Inc. | |||||||||
| Debt Instrument [Line Items] | |||||||||
| Long term debt | $ 300 | $ 101 | |||||||
| |||||||||
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- Definition Debt instrument maturity year No definition available.
|
| X | ||||||||||
- Definition Debt Instrument Unamortized Discount Premium and Debt Issuance Costs No definition available.
|
| X | ||||||||||
- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. No definition available.
|
| X | ||||||||||
- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Weighted average interest rate of long-term debt outstanding calculated at point in time. No definition available.
|
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Debt - Contractual Principal Payments under Outstanding Long-Term Debt Agreements (Details) - UAL and United - USD ($) $ in Millions |
Dec. 31, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Debt Instrument [Line Items] | ||
| 2019 | $ 1,230 | |
| 2020 | 1,310 | |
| 2021 | 1,300 | |
| 2022 | 1,653 | |
| 2023 | 703 | |
| After 2023 | 7,440 | |
| Long-term debt | $ 13,636 | $ 13,431 |
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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Debt - Narrative (Details) - USD ($) |
1 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|
Mar. 29, 2017 |
Sep. 30, 2017 |
Jan. 31, 2017 |
Dec. 31, 2018 |
|
| 4.25% Senior Notes due 2022 | ||||
| Debt Instrument [Line Items] | ||||
| Fixed interest rate | 4.25% | |||
| 5% Senior Notes due 2024 | ||||
| Debt Instrument [Line Items] | ||||
| Fixed interest rate | 5.00% | |||
| United Airlines, Inc. | ||||
| Debt Instrument [Line Items] | ||||
| Aggregate principal amount | $ 424,000,000 | |||
| United Airlines, Inc. | Pass-Through Certificates | ||||
| Debt Instrument [Line Items] | ||||
| Long term debt | 8,800,000,000 | |||
| United Airlines, Inc. | 4.25% Senior Notes due 2022 | ||||
| Debt Instrument [Line Items] | ||||
| Aggregate principal amount | $ 400,000,000 | |||
| Debt instrument maturity date | Oct. 01, 2022 | |||
| Fixed interest rate | 4.25% | |||
| Notes repurchase price | 101.00% | |||
| United Airlines, Inc. | 5% Senior Notes due 2024 | ||||
| Debt Instrument [Line Items] | ||||
| Aggregate principal amount | $ 300,000,000 | |||
| Debt instrument maturity date | Feb. 01, 2024 | |||
| Fixed interest rate | 5.00% | |||
| Notes repurchase price | 101.00% | |||
| United Airlines, Inc. | Surety Bond | ||||
| Debt Instrument [Line Items] | ||||
| Credit facility outstanding amount | $ 418,000,000 | |||
| Credit facility expiration year | 2022 | |||
| United Airlines, Inc. | Letters of Credit | Cash Collateralized Letters of Credit | ||||
| Debt Instrument [Line Items] | ||||
| Credit facility outstanding amount | $ 73,000,000 | |||
| United Airlines, Inc. | Secured Debt | ||||
| Debt Instrument [Line Items] | ||||
| Quarterly principal repayment amount | 0.25% | |||
| United Airlines, Inc. | Secured Debt | Term Loan due April 1, 2024 | LIBOR | ||||
| Debt Instrument [Line Items] | ||||
| Basis spread on variable rate | 1.75% | |||
| United Airlines, Inc. | Secured Debt | Term Loan due April 1, 2024 | Alternative Rate Based on Certain Market Interest Rates | ||||
| Debt Instrument [Line Items] | ||||
| Basis spread on variable rate | 0.75% | |||
| United Airlines, Inc. | Secured Debt | Term Loan due April 1, 2024 | ||||
| Debt Instrument [Line Items] | ||||
| Aggregate principal amount | $ 1,500,000,000 | |||
| Debt instrument maturity date | Apr. 01, 2024 | |||
| United Airlines, Inc. | Secured Debt | Revolving Credit Facility Available for Drawing until April 1, 2022 | ||||
| Debt Instrument [Line Items] | ||||
| Credit agreement | $ 2,000,000,000 | |||
| Revolving credit facility available for drawing date | Apr. 01, 2022 | |||
| United Airlines, Inc. | Secured Debt | Revolving Credit Facility | ||||
| Debt Instrument [Line Items] | ||||
| Commitment fee percentage | 0.75% | |||
| Available under revolving credit facility | $ 2,000,000,000 | |||
| United Airlines, Inc. | Secured Debt | Revolving Credit Facility | LIBOR | ||||
| Debt Instrument [Line Items] | ||||
| Basis spread on variable rate | 2.25% | |||
| United Airlines, Inc. | Secured Debt | Revolving Credit Facility | Alternative Rate Based on Certain Market Interest Rates | ||||
| Debt Instrument [Line Items] | ||||
| Basis spread on variable rate | 1.25% | |||
| X | ||||||||||
- Definition Line Of Credit Facility Maturity Year No definition available.
|
| X | ||||||||||
- Definition Longterm Debt Maturities Repayments of Principal in Quarterly Installments Percent No definition available.
|
| X | ||||||||||
- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. No definition available.
|
| X | ||||||||||
- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Percentage price of original principal amount of debt at which debt can be redeemed by the issuer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Date the credit facility terminates, in CCYY-MM-DD format. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility. No definition available.
|
| X | ||||||||||
- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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Debt - Details of Past Through Trusts (Details) - USD ($) |
12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Feb. 28, 2018 |
|||||||
| Debt Instrument [Line Items] | ||||||||||
| Proceeds received from issuance of debt | $ 1,740,000,000 | $ 2,765,000,000 | [1] | $ 808,000,000 | [1] | |||||
| EETC | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Principal | $ 1,000,000,000.0 | |||||||||
| United Airlines, Inc. | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Principal | 424,000,000 | |||||||||
| Proceeds received from issuance of debt | 1,740,000,000 | $ 2,765,000,000 | [2] | $ 808,000,000 | [2] | |||||
| United Airlines, Inc. | EETC | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Principal | 2,174,000,000 | |||||||||
| Total debt recorded | 1,161,000,000 | |||||||||
| Proceeds received from issuance of debt | 1,161,000,000 | |||||||||
| Remaining proceeds from issuance of debt to be received in future periods | 1,013,000,000 | |||||||||
| United Airlines, Inc. | AA | February 2019 | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Principal | $ 717,000,000 | |||||||||
| Stated interest rate | 4.15% | |||||||||
| Total debt recorded | $ 0 | |||||||||
| Proceeds received from issuance of debt | 0 | |||||||||
| Remaining proceeds from issuance of debt to be received in future periods | 717,000,000 | |||||||||
| United Airlines, Inc. | AA | February 2018 | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Principal | $ 677,000,000 | |||||||||
| Stated interest rate | 3.50% | |||||||||
| Total debt recorded | $ 677,000,000 | |||||||||
| Proceeds received from issuance of debt | 677,000,000 | |||||||||
| Remaining proceeds from issuance of debt to be received in future periods | 0 | |||||||||
| United Airlines, Inc. | A | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Principal | $ 296,000,000 | |||||||||
| Stated interest rate | 4.55% | |||||||||
| Total debt recorded | $ 0 | |||||||||
| Proceeds received from issuance of debt | 0 | |||||||||
| Remaining proceeds from issuance of debt to be received in future periods | 296,000,000 | |||||||||
| United Airlines, Inc. | A | February 2018 | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Principal | $ 258,000,000 | |||||||||
| Stated interest rate | 3.70% | |||||||||
| Total debt recorded | $ 258,000,000 | |||||||||
| Proceeds received from issuance of debt | 258,000,000 | |||||||||
| Remaining proceeds from issuance of debt to be received in future periods | 0 | |||||||||
| United Airlines, Inc. | B | May 2018 | ||||||||||
| Debt Instrument [Line Items] | ||||||||||
| Principal | $ 226,000,000 | |||||||||
| Stated interest rate | 4.60% | |||||||||
| Total debt recorded | $ 226,000,000 | |||||||||
| Proceeds received from issuance of debt | 226,000,000 | |||||||||
| Remaining proceeds from issuance of debt to be received in future periods | $ 0 | |||||||||
| ||||||||||
| X | ||||||||||
- Definition Amount of borrowing capacity currently available under the debt instrument (initial borrowing capacity less the amount of proceeds received). No definition available.
|
| X | ||||||||||
- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
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| X | ||||||||||
- Details
|
Debt - Summary of Collateral Covenants and Cross Default Provisions (Details) $ in Billions |
12 Months Ended |
|---|---|
|
Dec. 31, 2018
USD ($)
| |
| Credit Agreement | |
| Debt Instrument [Line Items] | |
| Unrestricted liquidity required for credit agreement | $ 2.0 |
| Minimum ratio of appraised value of collateral for Credit Agreement | 160.00% |
| 6.375% Senior Notes due 2018 | |
| Debt Instrument [Line Items] | |
| Fixed interest rate | 6.375% |
| Debt instrument maturity year | 2018 |
| 6% Senior Notes due 2020 | |
| Debt Instrument [Line Items] | |
| Fixed interest rate | 6.00% |
| Debt instrument maturity year | 2020 |
| 5% Senior Notes due 2024 | |
| Debt Instrument [Line Items] | |
| Fixed interest rate | 5.00% |
| Debt instrument maturity year | 2024 |
| 4.25% Senior Notes due 2022 | |
| Debt Instrument [Line Items] | |
| Fixed interest rate | 4.25% |
| Debt instrument maturity year | 2022 |
| X | ||||||||||
- Definition Debt Covenant, Required Liquidity No definition available.
|
| X | ||||||||||
- Definition Debt Instrument Maturity Date Year No definition available.
|
| X | ||||||||||
- Definition Minimum ratio of appraised value of collateral for Credit Agreement No definition available.
|
| X | ||||||||||
- Definition Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
Leases and Capacity Purchase Agreements - Future Minimum Lease Payments under Operating and Capital Leases (Details) - USD ($) $ in Millions |
Dec. 31, 2018 |
Dec. 31, 2017 |
[1] | ||
|---|---|---|---|---|---|
| Capital Leases | |||||
| 2019 | $ 308 | ||||
| 2020 | 170 | ||||
| 2021 | 147 | ||||
| 2022 | 123 | ||||
| 2023 | 104 | ||||
| After 2023 | 1,268 | ||||
| Minimum lease payments | 2,120 | ||||
| Imputed interest | (837) | ||||
| Present value of minimum lease payments | 1,283 | ||||
| Current portion | (149) | $ (128) | |||
| Long-term obligations under capital leases | 1,134 | $ 996 | |||
| Airport Construction Projects | |||||
| Operating Leases | |||||
| Operating property and equipment under capital leases | 886 | ||||
| Obligations under capital leases | 920 | ||||
| Facility and Other Operating Leases | |||||
| Operating Leases | |||||
| 2019 | 1,330 | ||||
| 2020 | 1,351 | ||||
| 2021 | 1,107 | ||||
| 2022 | 970 | ||||
| 2023 | 953 | ||||
| After 2023 | 7,029 | ||||
| Minimum lease payments | 12,740 | ||||
| Aircraft Operating Leases | |||||
| Operating Leases | |||||
| 2019 | 845 | ||||
| 2020 | 682 | ||||
| 2021 | 583 | ||||
| 2022 | 407 | ||||
| 2023 | 379 | ||||
| After 2023 | 1,160 | ||||
| Minimum lease payments | $ 4,056 | ||||
| |||||
| X | ||||||||||
- Definition Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of capital lease obligation due within one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal, through the balance sheet date and due to be paid more than one year (or one operating cycle, if longer) after the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of minimum lease payments for capital leases due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of minimum lease payments for capital leases due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of minimum lease payments for capital leases due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of minimum lease payments for capital leases due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of minimum lease payments for capital leases due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of minimum lease payments for capital leases due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount necessary to reduce net minimum lease payments to present value for capital leases. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of minimum lease payments for capital leases net of executory costs, which include amounts paid by the lessee to the lessor for insurance, maintenance and taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount after depreciation of long-lived, physical assets used to produce goods and services and not intended for resale, classified as other. No definition available.
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
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| X | ||||||||||
- Details
|
Leases and Capacity Purchase Agreements - Narrative (Details) $ in Millions |
12 Months Ended | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Dec. 31, 2019
USD ($)
|
Dec. 31, 2018
USD ($)
Aircraft
|
Dec. 31, 2017
USD ($)
|
Dec. 31, 2016
USD ($)
|
Dec. 31, 2015
USD ($)
|
|||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Regional capacity purchase expense | $ 2,601 | $ 2,232 | [1] | $ 2,197 | [1] | ||||||||||
| Expenses | 38,011 | 34,113 | [1] | 32,214 | [1] | ||||||||||
| Accounts payable | 2,363 | 2,196 | [2] | ||||||||||||
| Capacity Purchase Agreements | Forecast | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Scheduled block hours increase (decrease) percentage | 10.00% | ||||||||||||||
| Change in cash obligation | $ 160 | ||||||||||||||
| Aircraft Operating Leases | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Operating leases obligations | $ 4,056 | ||||||||||||||
| Minimum | Aircraft Operating Leases | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Operating lease term | 5 years | ||||||||||||||
| Operating lease expiration date | 2019 | ||||||||||||||
| Maximum | Aircraft Operating Leases | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Operating lease term | 26 years | ||||||||||||||
| Operating lease expiration date | 2029 | ||||||||||||||
| United Airlines, Inc. | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Nonaircraft rent expense | $ 1,300 | 1,300 | 1,200 | ||||||||||||
| Regional capacity purchase expense | $ 2,601 | 2,232 | [3] | 2,197 | [3] | ||||||||||
| Number of aircrafts under the extended term of contract | Aircraft | 125 | ||||||||||||||
| Capacity purchase agreement contract expiration date after extension | Dec. 31, 2022 | ||||||||||||||
| Expenses | $ 38,009 | 34,111 | [3] | 32,212 | [3] | ||||||||||
| Accounts payable | $ 2,363 | 2,196 | [4] | ||||||||||||
| United Airlines, Inc. | Capacity Purchase Agreements | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Number of regional aircraft | Aircraft | 559 | ||||||||||||||
| Airline capacity purchase arrangements, expiration year | 2029 | ||||||||||||||
| United Airlines, Inc. | Revaluation of Liabilities | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Net accretion amounts | $ 60 | 79 | $ 82 | ||||||||||||
| United Airlines, Inc. | Variable Interest Entity, Not Primary Beneficiary | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Operating leases obligations | 1,300 | ||||||||||||||
| United Airlines, Inc. | Regional Aircraft | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Regional capacity purchase expense | $ 505 | 458 | 439 | ||||||||||||
| United Airlines, Inc. | Minimum | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Imputed interest rate | 3.50% | ||||||||||||||
| Remaining lease term | 1 year | ||||||||||||||
| United Airlines, Inc. | Maximum | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Imputed interest rate | 115.10% | ||||||||||||||
| Remaining lease term | 6 years | ||||||||||||||
| United Airlines, Inc. | Mainline | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Number of assets subject to lease | Aircraft | 28 | ||||||||||||||
| United Airlines, Inc. | Regional Carrier | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Number of assets subject to lease | Aircraft | 90 | ||||||||||||||
| United Airlines, Inc. | Regional Carrier | Capacity Purchase Agreements | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Expenses | $ 979 | 907 | $ 935 | ||||||||||||
| Accounts payable | 53 | 24 | |||||||||||||
| Accounts receivable from regional carriers | $ 0 | $ 0 | |||||||||||||
| CRJ 200 | United Airlines, Inc. | Maximum | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Number of aircraft to operate | Aircraft | 65 | ||||||||||||||
| Chicago O'Hare | Airline Use and Lease Agreement - Chicago O'Hare | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Operating lease term | 15 years | ||||||||||||||
| Chicago O'Hare | Minimum | Hangars, Ground Equipment Maintenance Building and Employee Parking Lease | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Operating lease term | 15 years | ||||||||||||||
| Chicago O'Hare | Maximum | Hangars, Ground Equipment Maintenance Building and Employee Parking Lease | |||||||||||||||
| Capital Leased Assets [Line Items] | |||||||||||||||
| Operating lease term | 30 years | ||||||||||||||
| |||||||||||||||
| X | ||||||||||
- Definition Airline, Capacity Purchase Arrangements Expiration Year No definition available.
|
| X | ||||||||||
- Definition Capacity Purchase Agreement Contract Expiration Date After Extension No definition available.
|
| X | ||||||||||
- Definition Capital Lease Imputed Interest Rate No definition available.
|
| X | ||||||||||
- Definition Increase (Decrease) in Cash Obligation No definition available.
|
| X | ||||||||||
- Definition Lease Remaining Term No definition available.
|
| X | ||||||||||
- Definition Net Accretion Amounts of Noncurrent Deferred Finance Costs Liability No definition available.
|
| X | ||||||||||
- Definition Nonaircraft Rent Expense No definition available.
|
| X | ||||||||||
- Definition Number of aircraft to operate. No definition available.
|
| X | ||||||||||
- Definition The approximate number of aircraft whose term was extended under an existing contract. No definition available.
|
| X | ||||||||||
- Definition Number Of Assets Subject to Lease No definition available.
|
| X | ||||||||||
- Definition Operating Lease Expiration Year No definition available.
|
| X | ||||||||||
- Definition Scheduled Block Hours Increase (Decrease) Percentage No definition available.
|
| X | ||||||||||
- Definition Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Costs incurred related to air services provided by third-party transportation companies, including regional affiliates. No definition available.
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Total costs of sales and operating expenses for the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Number of aircraft operated by the carrier. No definition available.
|
| X | ||||||||||
- Definition Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
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| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
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| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
Leases and Capacity Purchase Agreements - Future Lease Payment under Terms of Capacity Purchase Agreement (Details) $ in Billions |
Dec. 31, 2018
USD ($)
|
|---|---|
| Leases [Abstract] | |
| 2019 | $ 2.2 |
| 2020 | 2.0 |
| 2021 | 1.8 |
| 2022 | 1.4 |
| 2023 | 0.8 |
| 2024 | 3.1 |
| Total | $ 11.3 |
| X | ||||||||||
- Definition Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments. No definition available.
|
| X | ||||||||||
- Definition Amount of contractual obligation due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
|
| X | ||||||||||
- Definition Amount of contractual obligation due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
|
| X | ||||||||||
- Definition Amount of contractual obligation due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
|
| X | ||||||||||
- Definition Amount of contractual obligation due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
|
| X | ||||||||||
- Definition Amount of contractual obligation due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
|
| X | ||||||||||
- Definition Amount of contractual obligation due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. No definition available.
|
| X | ||||||||||
- References No definition available.
|
Variable Interest Entities (Details) |
Dec. 31, 2018
aircraft
|
|---|---|
| Mainline | |
| Variable Interest Entity [Line Items] | |
| Aircraft under operating lease, fixed purchase options | 23 |
| Regional Carrier | |
| Variable Interest Entity [Line Items] | |
| Aircraft under operating lease | 90 |
| X | ||||||||||
- Definition Number of Aircraft under Operating Lease Agreements with Fixed Price Purchase Options No definition available.
|
| X | ||||||||||
- Definition Number of aircraft under operating lease agreements with purchase options at prices potentially below fair value. No definition available.
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
Commitments and Contingencies - Narrative (Details) $ / shares in Units, Employee in Thousands |
12 Months Ended | ||
|---|---|---|---|
|
Dec. 31, 2018
USD ($)
Employee
commitment
aircraft
Option
Aircraft
|
Nov. 29, 2018
USD ($)
$ / shares
shares
|
Feb. 28, 2018
USD ($)
|
|
| Commitments and Contingencies [Line Items] | |||
| Aggregate balance | $ 11,300,000,000 | ||
| Number of call options to purchase regional jet aircraft | Option | 292 | ||
| United Airlines, Inc. | |||
| Commitments and Contingencies [Line Items] | |||
| Debt instrument principal amount | $ 424,000,000 | ||
| Number of employees | Employee | 92 | ||
| Percentage of employees represented by various U.S. labor organizations | 83.00% | ||
| Tax-Exempt Special Facilities Revenue Bonds | |||
| Commitments and Contingencies [Line Items] | |||
| Guarantor obligations, maximum exposure | $ 1,900,000,000.0 | ||
| Operating leases obligations | 1,300,000,000 | ||
| Capital leases obligations | 466,000,000 | ||
| Tax-Exempt Special Facilities Revenue Bonds | Indirect Guarantee of Indebtedness | |||
| Commitments and Contingencies [Line Items] | |||
| Guarantor obligations, maximum exposure | 164,000,000 | ||
| Contingent liabilities based on participation | 1,700,000,000 | ||
| Floating Rate Debt | |||
| Commitments and Contingencies [Line Items] | |||
| Debt instrument principal amount | 3,500,000,000.0 | ||
| Fixed Rate Debt | |||
| Commitments and Contingencies [Line Items] | |||
| Debt instrument principal amount | 27,000,000 | ||
| Loans And Leases From Non U S Entities | |||
| Commitments and Contingencies [Line Items] | |||
| Aggregate balance | 3,200,000,000 | ||
| Aircraft Mortgage Debt | |||
| Commitments and Contingencies [Line Items] | |||
| Guarantor obligations, maximum exposure | $ 145,000,000 | ||
| Minimum | Tax-Exempt Special Facilities Revenue Bonds | |||
| Commitments and Contingencies [Line Items] | |||
| Maturity date | 2019 | ||
| Minimum | Tax-Exempt Special Facilities Revenue Bonds | Indirect Guarantee of Indebtedness | |||
| Commitments and Contingencies [Line Items] | |||
| Maturity date | 2022 | ||
| Maximum | |||
| Commitments and Contingencies [Line Items] | |||
| Debt instrument, remaining terms | 12 years | ||
| Maximum | Tax-Exempt Special Facilities Revenue Bonds | |||
| Commitments and Contingencies [Line Items] | |||
| Maturity date | 2038 | ||
| Maximum | Tax-Exempt Special Facilities Revenue Bonds | Indirect Guarantee of Indebtedness | |||
| Commitments and Contingencies [Line Items] | |||
| Maturity date | 2051 | ||
| Maximum | Loans And Leases From Non U S Entities | |||
| Commitments and Contingencies [Line Items] | |||
| Debt instrument, remaining terms | 12 years | ||
| Kingsland | |||
| Commitments and Contingencies [Line Items] | |||
| Number of shares that may be put to United (in shares) | shares | 144,800,000.0 | ||
| Number of ADRs that may be put to United (in shares) | shares | 18,100,000 | ||
| Market price of common stock at fifth anniversary (in dollars per share) | $ / shares | $ 12 | ||
| Aggregate maximum possible combined put payment and guarantee amount | $ 217,200,000 | ||
| Contingent liabilities based on participation | $ 31,000,000 | ||
| EETC | |||
| Commitments and Contingencies [Line Items] | |||
| Debt instrument principal amount | $ 1,000,000,000.0 | ||
| EETC | United Airlines, Inc. | |||
| Commitments and Contingencies [Line Items] | |||
| Debt instrument principal amount | $ 2,174,000,000 | ||
| Embraer E175 | |||
| Commitments and Contingencies [Line Items] | |||
| Number of aircrafts expects to take delivery | Aircraft | 25 | ||
| Number of firm commitments | commitment | 25 | ||
| Boeing 737 MAX | |||
| Commitments and Contingencies [Line Items] | |||
| Number of aircrafts expects to take delivery | Aircraft | 20 | ||
| Boeing 787 | |||
| Commitments and Contingencies [Line Items] | |||
| Number of aircrafts expects to take delivery | Aircraft | 8 | ||
| Boeing 777-300ER | |||
| Commitments and Contingencies [Line Items] | |||
| Number of aircraft expected to be delivered | aircraft | 2 | ||
| Airbus A319s | |||
| Commitments and Contingencies [Line Items] | |||
| Number of firm commitments | aircraft | 20 | ||
| Embraer ERJ 145 | |||
| Commitments and Contingencies [Line Items] | |||
| Number of aircraft under lease | aircraft | 54 |
| X | ||||||||||
- Definition Number of persons employed by the Entity No definition available.
|
| X | ||||||||||
- Definition Capital Leased Assets, Number Of Aircraft No definition available.
|
| X | ||||||||||
- Definition Commitments And Contingencies [Line Items] No definition available.
|
| X | ||||||||||
- Definition Debt instrument maturity year No definition available.
|
| X | ||||||||||
- Definition Years remaining on debt instruments. No definition available.
|
| X | ||||||||||
- Definition Loans Receivable, Aggregate Maximum Payment And Guarantee Amount No definition available.
|
| X | ||||||||||
- Definition Loans Receivable, Agreement, Put Option, Deposit Receipts No definition available.
|
| X | ||||||||||
- Definition Loans Receivable, Agreement, Put Options No definition available.
|
| X | ||||||||||
- Definition Loans Receivable, Guarantee And Payout Share Price At Fifth Anniversary No definition available.
|
| X | ||||||||||
- Definition Number of Aircraft Expected to Be Delivered No definition available.
|
| X | ||||||||||
- Definition Number of aircrafts expected to take delivery. No definition available.
|
| X | ||||||||||
- Definition Number of Call Options To Purchase Regional Jet Aircraft No definition available.
|
| X | ||||||||||
- Definition Percentage of employees represented by labor organizations No definition available.
|
| X | ||||||||||
- Definition Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments. No definition available.
|
| X | ||||||||||
- Definition Face (par) amount of debt instrument at time of issuance. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The minimum number of units that must be purchased, in connection with an unconditional purchase obligation that has not been recognized for financial reporting purposes. No definition available.
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
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| X | ||||||||||
- Details
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| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
Commitments and Contingencies - Firm Commitments and Options to Purchase Aircraft (Details) |
Dec. 31, 2018
commitment
|
|---|---|
| Airbus A350 | |
| Long-term Purchase Commitment [Line Items] | |
| Number aircraft under purchase agreements | 45 |
| Boeing 737 MAX | |
| Long-term Purchase Commitment [Line Items] | |
| Number aircraft under purchase agreements | 175 |
| Boeing 777-300ER | |
| Long-term Purchase Commitment [Line Items] | |
| Number aircraft under purchase agreements | 4 |
| Boeing 787 | |
| Long-term Purchase Commitment [Line Items] | |
| Number aircraft under purchase agreements | 24 |
| Embraer E175 | |
| Long-term Purchase Commitment [Line Items] | |
| Number aircraft under purchase agreements | 25 |
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition The minimum number of units that must be purchased, in connection with an unconditional purchase obligation that has not been recognized for financial reporting purposes. No definition available.
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|
Commitments and Contingencies - Summary of Commitments Related to the Acquisition of Aircraft (Details) $ in Billions |
Dec. 31, 2018
USD ($)
|
|---|---|
| Commitments and Contingencies Disclosure [Abstract] | |
| 2019 | $ 4.2 |
| 2020 | 5.3 |
| 2021 | 3.5 |
| 2022 | 2.8 |
| 2023 | 1.9 |
| After 2023 | 7.0 |
| Total | $ 24.7 |
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of the unrecorded obligation to transfer funds in the future for fixed or minimum amounts or quantities of goods or services at fixed or minimum prices (for example, as in take-or-pay contracts or throughput contracts). Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
Special Charges - Components of Special Charges (Details) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|||||
| Operating: | |||||||||||||||
| Impairment of assets | $ 232 | $ 11 | $ 111 | $ 23 | $ 10 | $ 15 | $ 0 | $ 0 | $ 377 | $ 25 | $ 412 | ||||
| Termination of an engine maintenance service agreement | 64 | 0 | 0 | 0 | 64 | 0 | 0 | ||||||||
| Severance and benefit costs | 7 | 9 | 11 | 14 | 15 | 23 | 41 | 37 | 41 | 116 | 37 | ||||
| Cleveland airport lease restructuring | 0 | 0 | 74 | ||||||||||||
| Labor agreement costs | 0 | 0 | 171 | ||||||||||||
| (Gains) losses on sale of assets and other special charges | (2) | (3) | 7 | 3 | 6 | 12 | 3 | 14 | 5 | 35 | 51 | ||||
| Total operating special charges | 301 | 17 | 129 | 40 | 31 | 50 | 44 | 51 | 487 | 176 | [1] | 745 | [1] | ||
| Nonoperating income (expense): | |||||||||||||||
| Postretirement curtailment gain | 0 | 0 | (107) | ||||||||||||
| Gains on extinguishment of debt and other | 0 | 0 | (1) | ||||||||||||
| Total operating and nonoperating special charges before income taxes | 487 | 176 | 637 | ||||||||||||
| Nonoperating mark-to-market (MTM) losses on financial instruments | (56) | (29) | 135 | (45) | 5 | 0 | 0 | ||||||||
| Total special charges and MTM (gains) losses on financial instruments | 245 | (12) | 264 | (5) | 492 | 176 | 637 | ||||||||
| Income tax benefit | (55) | 3 | (59) | 1 | (11) | (18) | (16) | (18) | (110) | (63) | (229) | ||||
| Income tax adjustments | (5) | 0 | 0 | 0 | (179) | 0 | 0 | 0 | (5) | (179) | 180 | ||||
| Total operating special charges, net of income taxes and income tax adjustments | $ 185 | $ (9) | $ 205 | $ (4) | $ (159) | $ 32 | $ 28 | $ 33 | $ 377 | $ (66) | $ 588 | ||||
| |||||||||||||||
| X | ||||||||||
- Definition Gain (Loss) On Financial Instruments, Nonoperating No definition available.
|
| X | ||||||||||
- Definition Amount of gain (loss) on sale of other assets and other miscellaneous charges. No definition available.
|
| X | ||||||||||
- Definition Income tax adjustments that include items such as deferred income tax expense in AOCI and valuation allowance adjustments. No definition available.
|
| X | ||||||||||
- Definition Income tax expense (benefit) special charges. No definition available.
|
| X | ||||||||||
- Definition Bonus payments made to employees in conjunction with the ratification of employment contracts. No definition available.
|
| X | ||||||||||
- Definition Special Charges And Losses On Financial Instruments, Nonoperating, Before Tax No definition available.
|
| X | ||||||||||
- Definition Special items before income taxes. No definition available.
|
| X | ||||||||||
- Definition Total special items in the period. No definition available.
|
| X | ||||||||||
- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The loss recognized on termination of a contract. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Period expense related to postemployment benefits. No definition available.
|
| X | ||||||||||
- Definition Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Amount of restructuring charges, remediation cost, and asset impairment loss. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
Special Charges - Narrative (Details) |
1 Months Ended | 3 Months Ended | 12 Months Ended | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
May 31, 2018
USD ($)
|
Dec. 31, 2018
USD ($)
|
Sep. 30, 2018
USD ($)
|
Jun. 30, 2018
USD ($)
|
Mar. 31, 2018
USD ($)
|
Dec. 31, 2017
USD ($)
|
Sep. 30, 2017
USD ($)
|
Jun. 30, 2017
USD ($)
|
Mar. 31, 2017
USD ($)
|
Dec. 31, 2018
USD ($)
|
Dec. 31, 2017
USD ($)
Contract
|
Dec. 31, 2016
USD ($)
|
Dec. 31, 2014
USD ($)
|
|
| Special Charges [Line Items] | |||||||||||||
| Fair value adjustments related to aircraft purchased off lease, write-off of unexercised aircraft purchase options and other impairments | $ 66,000,000 | ||||||||||||
| Fair value adjustments related to aircraft purchased off lease, write-off of unexercised aircraft purchase options and other impairments, net of tax | 51,000,000 | ||||||||||||
| Termination of an engine maintenance service agreement | $ 64,000,000 | $ 0 | $ 0 | $ 0 | 64,000,000 | $ 0 | $ 0 | ||||||
| Termination of an engine maintenance service agreement, net of tax | 50,000,000 | ||||||||||||
| Severance and benefit costs | 7,000,000 | 9,000,000 | 11,000,000 | 14,000,000 | $ 15,000,000 | $ 23,000,000 | $ 41,000,000 | $ 37,000,000 | 41,000,000 | 116,000,000 | 37,000,000 | ||
| Gain on change in market value of equity investments | 28,000,000 | ||||||||||||
| Gain on change in market value of equity investments, net of tax | 22,000,000 | ||||||||||||
| Losses due to the change in fair value of derivatives | 33,000,000 | ||||||||||||
| Losses due to the change in fair value of derivatives, net of tax | 26,000,000 | ||||||||||||
| Impairment of assets | 232,000,000 | $ 11,000,000 | $ 111,000,000 | $ 23,000,000 | $ 10,000,000 | 15,000,000 | $ 0 | 0 | 377,000,000 | 25,000,000 | 412,000,000 | ||
| Cleveland airport lease restructuring | 0 | 0 | 74,000,000 | ||||||||||
| Cleveland airport lease restructuring, net of taxes | 47,000,000 | ||||||||||||
| Labor agreement costs | 0 | 0 | 171,000,000 | ||||||||||
| Curtailment gain recognition of prior service credit | 0 | 0 | 107,000,000 | ||||||||||
| Postretirement Medical Plan | Flight Attendant Postretirement Medical Plan | |||||||||||||
| Special Charges [Line Items] | |||||||||||||
| Curtailment gain recognition of prior service credit | 47,000,000 | ||||||||||||
| Curtailment gain recognition of prior service credit, net of tax | 30,000,000 | ||||||||||||
| Newark Liberty International Airport | |||||||||||||
| Special Charges [Line Items] | |||||||||||||
| Impairment of indefinite-lived intangible assets | 412,000,000 | ||||||||||||
| Impairment of indefinite-lived intangible assets, net of tax benefits | 264,000,000 | ||||||||||||
| Voluntary Early Out Program | |||||||||||||
| Special Charges [Line Items] | |||||||||||||
| Severance and benefit costs | 37,000,000 | ||||||||||||
| Severance and benefits costs, net of tax | 24,000,000 | ||||||||||||
| Obsolete Spare Parts Inventory | |||||||||||||
| Special Charges [Line Items] | |||||||||||||
| Impairment of assets | 10,000,000 | ||||||||||||
| Impairment of assets, net of tax | 6,000,000 | ||||||||||||
| Maintenance Service Agreement | |||||||||||||
| Special Charges [Line Items] | |||||||||||||
| Intangible assets impairment charge | 15,000,000 | ||||||||||||
| Intangible assets impairment charge, net of tax | $ 10,000,000 | ||||||||||||
| Management Reorganization Initiative | |||||||||||||
| Special Charges [Line Items] | |||||||||||||
| Severance and benefit costs | 33,000,000 | ||||||||||||
| Severance and benefits costs, net of tax | 21,000,000 | ||||||||||||
| International Brotherhood of Teamsters | |||||||||||||
| Special Charges [Line Items] | |||||||||||||
| Severance and benefit costs | 22,000,000 | 83,000,000 | |||||||||||
| Severance and benefits costs, net of tax | 17,000,000 | $ 53,000,000 | |||||||||||
| International Brotherhood of Teamsters | Maximum | Voluntary Early Out Program | |||||||||||||
| Special Charges [Line Items] | |||||||||||||
| Severance payment per participant | $ 100,000 | $ 100,000 | |||||||||||
| Int'l Association of Machinists | |||||||||||||
| Special Charges [Line Items] | |||||||||||||
| Number of new contracts extended | Contract | 7 | ||||||||||||
| Service contract extended year | 2021 | ||||||||||||
| Labor agreement costs | 171,000,000 | ||||||||||||
| Labor agreement costs, net of tax | 110,000,000 | ||||||||||||
| Curtailment gain recognition of prior service credit | 60,000,000 | ||||||||||||
| Curtailment gain recognition of prior service credit, net of tax | $ 38,000,000 | ||||||||||||
| Management | |||||||||||||
| Special Charges [Line Items] | |||||||||||||
| Severance and benefit costs | 19,000,000 | ||||||||||||
| Severance and benefits costs, net of tax | $ 15,000,000 | ||||||||||||
| Hong Kong Routes | |||||||||||||
| Special Charges [Line Items] | |||||||||||||
| Intangible assets impairment charge | 206,000,000 | ||||||||||||
| Intangible assets impairment charge, net of tax | $ 160,000,000 | ||||||||||||
| Brazil Routes | |||||||||||||
| Special Charges [Line Items] | |||||||||||||
| Intangible assets impairment charge | $ 105,000,000 | ||||||||||||
| Intangible assets impairment charge, net of tax | $ 82,000,000 | ||||||||||||
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- Definition Asset Impairment Charges, Net Of Tax No definition available.
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| X | ||||||||||
- Definition Defined Benefit Plan Recognized Net Gain Loss Due To Curtailments Net Of Tax No definition available.
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| X | ||||||||||
- Definition Derivative, Loss On Derivative, Net Of Tax No definition available.
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- Definition Equity Securities, FV-NI, Gain (Loss), Net Of Tax No definition available.
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- Definition Equity Securities, FV-NI, Gain (Loss) No definition available.
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| X | ||||||||||
- Definition Impairment Of Intangible Assets (Excluding Goodwill), Net Of Tax No definition available.
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| X | ||||||||||
- Definition Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill), Net of Tax No definition available.
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- Definition Bonus payments made to employees in conjunction with the ratification of employment contracts. No definition available.
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- Definition Bonus payments made to employees in conjunction with the ratification of employment contracts, net of tax. No definition available.
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- Definition Loss On Contract Termination, Net Of Tax No definition available.
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- Definition New Contracts Extended, Maturity Year No definition available.
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- Definition Number of Contracts Extended No definition available.
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- Definition Period expense related to postemployment benefits, net of tax. No definition available.
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| X | ||||||||||
- Definition Amount of expenses associated with exit or disposal activities pursuant to an authorized plan, net of tax. Excludes expenses related to a discontinued operation or an asset retirement obligation. No definition available.
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| X | ||||||||||
- Definition Special Charges, Fair Value Adjustment, Write-Offs, And Impairments Of Aircraft No definition available.
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| X | ||||||||||
- Definition Special Charges, Fair Value Adjustment, Write-Offs, And Impairments Of Aircraft, Net Of Tax No definition available.
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| X | ||||||||||
- Definition Special Charges [Line Items] No definition available.
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| X | ||||||||||
- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of decrease in the fair value of derivatives recognized in the income statement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of impairment loss resulting from write-down of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit to fair value. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The loss recognized on termination of a contract. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Period expense related to postemployment benefits. No definition available.
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| X | ||||||||||
- Definition Amount expected to be recognized in earnings for the specified restructuring cost. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Special Charges - Activity Related to the Accruals for Severance and Medical Costs and Future Lease Payments (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Severance/ Benefit Costs | |||
| Schedule Of Accrual Activity [Line Items] | |||
| Balance | $ 37 | $ 14 | $ 27 |
| Accrual and related adjustments | 41 | 116 | 37 |
| Payments | (53) | (93) | (50) |
| Balance | 25 | 37 | 14 |
| Permanently Grounded Aircraft | |||
| Schedule Of Accrual Activity [Line Items] | |||
| Balance | 22 | 41 | 78 |
| Accrual and related adjustments | (7) | (4) | (17) |
| Payments | (3) | (15) | (20) |
| Balance | $ 12 | $ 22 | $ 41 |
| X | ||||||||||
- Definition Schedule of Accrual Activity [Line Items] No definition available.
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| X | ||||||||||
- Definition Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Selected Quarterly Financial Data (Unaudited) - Summary of Selected Quarterly FInancial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2018 |
Dec. 31, 2017 |
[1] | Dec. 31, 2016 |
[1] | |||||||||
| Quarterly Financial Information Disclosure [Abstract] | |||||||||||||||||||||
| Operating revenue | $ 10,491 | $ 11,003 | $ 10,777 | $ 9,032 | $ 9,451 | $ 9,899 | $ 10,008 | $ 8,426 | $ 41,303 | $ 37,784 | $ 36,558 | ||||||||||
| Operating income | 652 | 1,203 | 1,161 | 276 | 776 | 1,138 | 1,437 | 320 | 3,292 | 3,671 | 4,344 | ||||||||||
| Net income | $ 462 | $ 836 | $ 684 | $ 147 | $ 579 | $ 645 | $ 821 | $ 99 | $ 2,129 | $ 2,144 | [2],[3],[4] | $ 2,234 | [2],[3],[4] | ||||||||
| Earnings per share, basic (in dollars per share) | $ 1.71 | $ 3.07 | $ 2.49 | $ 0.52 | $ 1.99 | $ 2.15 | $ 2.67 | $ 0.32 | $ 7.73 | $ 7.08 | $ 6.77 | ||||||||||
| Earnings per share, diluted (in dollars per share) | $ 1.70 | $ 3.06 | $ 2.48 | $ 0.52 | $ 1.98 | $ 2.15 | $ 2.67 | $ 0.32 | $ 7.70 | $ 7.06 | $ 6.76 | ||||||||||
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The net result for the period of deducting operating expenses from operating revenues. No definition available.
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| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Selected Quarterly Financial Data (Unaudited) - Impact of Significant Items on Quarterly Results (Details) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|||||
| Operating: | |||||||||||||||
| Impairment of assets | $ 232 | $ 11 | $ 111 | $ 23 | $ 10 | $ 15 | $ 0 | $ 0 | $ 377 | $ 25 | $ 412 | ||||
| Termination of an engine maintenance service agreement | 64 | 0 | 0 | 0 | 64 | 0 | 0 | ||||||||
| Severance and benefit costs | 7 | 9 | 11 | 14 | 15 | 23 | 41 | 37 | 41 | 116 | 37 | ||||
| (Gains) losses on sale of assets and other special charges | (2) | (3) | 7 | 3 | 6 | 12 | 3 | 14 | 5 | 35 | 51 | ||||
| Total operating special charges | 301 | 17 | 129 | 40 | 31 | 50 | 44 | 51 | 487 | 176 | [1] | 745 | [1] | ||
| Nonoperating income (expense): | |||||||||||||||
| Nonoperating mark-to-market (MTM) (gains) losses on financial instruments | (56) | (29) | 135 | (45) | 5 | 0 | 0 | ||||||||
| Total special charges and MTM (gains) losses on financial instruments | 245 | (12) | 264 | (5) | 492 | 176 | 637 | ||||||||
| Income taxes: | |||||||||||||||
| Income tax benefit related to special charges | (55) | 3 | (59) | 1 | (11) | (18) | (16) | (18) | (110) | (63) | (229) | ||||
| Income tax adjustments | (5) | 0 | 0 | 0 | (179) | 0 | 0 | 0 | (5) | (179) | 180 | ||||
| Total operating special charges, net of income taxes and income tax adjustments | $ 185 | $ (9) | $ 205 | $ (4) | $ (159) | $ 32 | $ 28 | $ 33 | $ 377 | $ (66) | $ 588 | ||||
| |||||||||||||||
| X | ||||||||||
- Definition Gain (Loss) On Financial Instruments, Nonoperating No definition available.
|
| X | ||||||||||
- Definition Amount of gain (loss) on sale of other assets and other miscellaneous charges. No definition available.
|
| X | ||||||||||
- Definition Income tax adjustments that include items such as deferred income tax expense in AOCI and valuation allowance adjustments. No definition available.
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| X | ||||||||||
- Definition Income tax expense (benefit) special charges. No definition available.
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| X | ||||||||||
- Definition Income Taxes [Abstract] No definition available.
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| X | ||||||||||
- Definition Special Charges And Losses On Financial Instruments, Nonoperating, Before Tax No definition available.
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| X | ||||||||||
- Definition Total special items in the period. No definition available.
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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The loss recognized on termination of a contract. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- References No definition available.
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- Definition Period expense related to postemployment benefits. No definition available.
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| X | ||||||||||
- Definition Amount of restructuring charges, remediation cost, and asset impairment loss. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Schedule II - Valuation and Qualifying Accounts (Details) - UAL and United - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Allowance for doubtful accounts | |||
| Valuation and Qualifying Accounts Disclosure [Line Items] | |||
| Balance at Beginning of Period | $ 7 | $ 10 | $ 18 |
| Additions Charged to Costs and Expenses | 17 | 20 | 18 |
| Deductions | 16 | 23 | 26 |
| Other | 0 | 0 | 0 |
| Balance at End of Period | 8 | 7 | 10 |
| Obsolescence allowance-spare parts | |||
| Valuation and Qualifying Accounts Disclosure [Line Items] | |||
| Balance at Beginning of Period | 354 | 295 | 235 |
| Additions Charged to Costs and Expenses | 73 | 75 | 61 |
| Deductions | 15 | 17 | 16 |
| Other | 0 | 1 | 15 |
| Balance at End of Period | 412 | 354 | 295 |
| Valuation allowance for deferred tax assets | |||
| Valuation and Qualifying Accounts Disclosure [Line Items] | |||
| Balance at Beginning of Period | 63 | 68 | 48 |
| Additions Charged to Costs and Expenses | 2 | 11 | 47 |
| Deductions | 6 | 27 | 27 |
| Other | 0 | 11 | 0 |
| Balance at End of Period | $ 59 | $ 63 | $ 68 |
| X | ||||||||||
- Definition Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to costs and expenses. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to accounts other than costs and expenses. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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| X | ||||||||||
- Definition Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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| Label | Element | Value |
|---|---|---|
| United Air Lines Inc [Member] | ||
| Cumulative Effect of New Accounting Principle in Period of Adoption | us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption | $ (14,000,000) |
| AOCI Attributable to Parent [Member] | ||
| Cumulative Effect of New Accounting Principle in Period of Adoption | us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption | 6,000,000 |
| Retained Earnings [Member] | United Air Lines Inc [Member] | ||
| Cumulative Effect of New Accounting Principle in Period of Adoption | us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption | $ (14,000,000) |
| X | ||||||||||
- Definition Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption. No definition available.
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