Employee Benefit Plans - Schedule of Changes in Projected Benefit Obligations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pension Benefits
Reconciliation of benefit obligation:
Benefit obligation at beginning of period	$ 14,037	$ 18,910
Service cost	2	3	$ 4
Interest cost	758	556	526
Actuarial loss (gain)	507	(4,563)
Plan amendments	0	0
Other	0	0
Benefit payments	(894)	(869)
Benefit obligation at end of period	14,410	14,037	18,910
Retiree Medical and  Other Postretirement Benefits
Reconciliation of benefit obligation:
Benefit obligation at beginning of period	906	1,098
Service cost	17	16	12
Interest cost	55	30	30
Actuarial loss (gain)	92	(167)
Plan amendments	339	0
Other	0	3
Benefit payments	(84)	(74)
Benefit obligation at end of period	1,325	906	1,098
American Airlines, Inc. | Pension Benefits
Reconciliation of benefit obligation:
Benefit obligation at beginning of period	13,948	18,791
Service cost	2	3	3
Interest cost	753	552	523
Actuarial loss (gain)	501	(4,534)
Plan amendments	0	0
Other	0	0
Benefit payments	(890)	(864)
Benefit obligation at end of period	14,314	13,948	18,791
American Airlines, Inc. | Retiree Medical and  Other Postretirement Benefits
Reconciliation of benefit obligation:
Benefit obligation at beginning of period	906	1,098
Service cost	17	16	12
Interest cost	55	30	30
Actuarial loss (gain)	92	(167)
Plan amendments	339	0
Other	0	3
Benefit payments	(84)	(74)
Benefit obligation at end of period	$ 1,325	$ 906	$ 1,098