Supplemental Financial Information - Accounts Payable (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accounts payable trade	$ 329	$ 277
Salaries, withholdings and payroll taxes	338	456
Ticket taxes and fees	357	242
Aircraft maintenance payable	121	65
Fuel payable	153	188
Dividends payable	0	107
Customer reimbursements and refunds	6	311
Accrued third party services	225	196
Other payable	207	162
Accounts payable	$ 1,736	$ 2,004