v3.19.2
Document and Entity Information - shares
6 Months Ended
Jun. 30, 2019
Jul. 12, 2019
Entity Information [Line Items]    
Document Type 10-Q  
Document Fiscal Period Focus Q2  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2019  
Document Transition Report false  
Amendment Flag false  
Document Fiscal Year Focus 2019  
Current Fiscal Year End Date --12-31  
Entity File Number 001-06033  
Entity Registrant Name United Airlines Holdings, Inc.  
Entity Central Index Key 0000100517  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 36-2675207  
Entity Information, Former Legal or Registered Name United Continental Holdings, Inc.  
Entity Address, Address Line One 233 South Wacker Drive,  
Entity Address, City or Town Chicago  
Entity Address, State or Province IL  
Entity Address, Postal Zip Code 60606  
City Area Code (872)  
Local Phone Number 825-4000  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Title of 12(b) Security Common Stock,  
Trading Symbol UAL  
Security Exchange Name NASDAQ  
Entity Common Stock, Shares Outstanding   256,921,469
United Airlines, Inc.    
Entity Information [Line Items]    
Entity File Number 001-10323  
Entity Registrant Name United Airlines, Inc.  
Entity Central Index Key 0000319687  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 74-2099724  
Entity Address, Address Line One 233 South Wacker Drive,  
Entity Address, City or Town Chicago  
Entity Address, State or Province IL  
Entity Address, Postal Zip Code 60606  
City Area Code (872)  
Local Phone Number 825-4000  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   1,000