Revenue - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Jul. 28, 2022	Dec. 31, 2021	Dec. 31, 2019
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Residual travel funds	5.00%		5.00%			16.00%	2.00%
Remaining customer travel funds	$ 1,100		$ 1,100
Loyalty points, redemption period (in years)			2 years
Total operating revenues	6,728	$ 4,008	$ 11,422	$ 6,060
Subsequent Event
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Remaining customer travel funds					$ 1,900
Chase Bank USA Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Total operating revenues	$ 522	$ 352	$ 1,000	$ 632