Employee Benefit Plans - Components of Net Periodic Benefit Cost (Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pension Benefits
Defined benefit plans:
Service cost	$ 2	$ 3	$ 4
Interest cost	758	556	526
Expected return on assets	(918)	(1,138)	(1,084)
Special termination benefits	0	0	0
Amortization of:
Prior service cost (benefit)	18	28	28
Unrecognized net loss (gain)	106	156	212
Net periodic benefit cost (income)	(34)	(395)	(314)
Retiree Medical and  Other Postretirement Benefits
Defined benefit plans:
Service cost	17	16	12
Interest cost	55	30	30
Expected return on assets	(11)	(12)	(12)
Special termination benefits	0	0	139
Amortization of:
Prior service cost (benefit)	(6)	(14)	(13)
Unrecognized net loss (gain)	(34)	(30)	(24)
Net periodic benefit cost (income)	21	(10)	132
American Airlines, Inc. | Pension Benefits
Defined benefit plans:
Service cost	2	3	3
Interest cost	753	552	523
Expected return on assets	(914)	(1,133)	(1,078)
Special termination benefits	0	0	0
Amortization of:
Prior service cost (benefit)	18	28	28
Unrecognized net loss (gain)	106	156	211
Net periodic benefit cost (income)	(35)	(394)	(313)
American Airlines, Inc. | Retiree Medical and  Other Postretirement Benefits
Defined benefit plans:
Service cost	17	16	12
Interest cost	55	30	30
Expected return on assets	(11)	(12)	(12)
Special termination benefits	0	0	139
Amortization of:
Prior service cost (benefit)	(6)	(14)	(13)
Unrecognized net loss (gain)	(34)	(30)	(24)
Net periodic benefit cost (income)	$ 21	$ (10)	$ 132