XML 54 R30.htm IDEA: XBRL DOCUMENT v3.21.2
REVENUE FROM CONTRACTS WITH CUSTOMERS - Narrative (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Jun. 30, 2021
Jun. 30, 2020
Dec. 31, 2020
Deferred Revenue Arrangement [Line Items]          
Receivable $ 567   $ 567   $ 480
Costs and Expenses 978 $ 709 1,936 $ 2,666  
COVID-19 Credits Issued, Balance 387   387    
Mileage Plan Revenue [Member]          
Deferred Revenue Arrangement [Line Items]          
Receivable 61   61   $ 48
Mileage Plan Revenue [Member] | Mileage plan other revenue [Member]          
Deferred Revenue Arrangement [Line Items]          
Contract liability revenue recognized     (17) (21)  
Passenger Revenue [Member]          
Deferred Revenue Arrangement [Line Items]          
Contract liability revenue recognized $ 36   $ 175 $ 484