Revenue - Air Traffic Liability - Loyalty Program Rollforward (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Change in Contract With Customer, Liability [Roll Forward]
Beginning balance	$ 4,885	$ 4,719	$ 4,789	$ 4,447
Amounts deferred associated with points awarded	815	688	2,395	1,810
Ending balance	4,885	4,772	4,885	4,772
Passenger Customer
Change in Contract With Customer, Liability [Roll Forward]
Revenue recognized from points redeemed	(791)	(621)	(2,236)	(1,448)
Other
Change in Contract With Customer, Liability [Roll Forward]
Revenue recognized from points redeemed	$ (24)	$ (14)	$ (63)	$ (37)