Other Current Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2023	Dec. 31, 2022
Other Liabilities Disclosure [Abstract]
Passenger and other taxes and fees payable	$ 128	$ 113
Salaries, wages and benefits	98	104
Aircraft maintenance	58	63
Station obligations	49	57
Fuel liabilities	33	34
Leased aircraft return costs	28	84
Other current liabilities	62	63
Total other current liabilities	$ 456	$ 518