Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Dec. 31, 2018
Revenue from Contract with Customer, Excluding Assessed Tax	$ 145	$ 1,936	$ 1,553	$ 3,649
Passenger Revenue - Loyalty Air Travel	25	95	129	184
Other Revenue - Loyalty	38	49	88	93
Other Revenue - Non Loyalty	7	25	33	51
Revenue from Contract with Customer, Excluding Assessed Tax	215	2,105	1,803	3,977
Air Traffic Liability - Passenger Travel	1,047		1,047		$ 929
Air Traffic Liability - Loyalty Program (Air Transportation)	676		676		661
Other Deferred Revenue	40		40		10
Contract with Customer, Liability	1,763		1,763		1,600
Contract with Customer, Liability, Revenue Recognized			666	819
Air Traffic Liability	676	$ 617	676	617	$ 661	$ 580
Increase (Decrease) to Air Traffic Liability - Points Redeemed			(129)	(184)
Increase (Decrease) to Air Traffic Liability - Points Earned			144	$ 221
Loyalty points, pre-purchase arrangement			150
Loyalty points, pre-purchase arrangement, carrying value	$ 113		$ 113
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-06-30
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	3 years		3 years

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.

No definition available.