Employee Benefit Plans - Components of Net Periodic Benefit Cost (Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1	$ 0	$ 1	$ 1
Interest cost	183	181	367	362
Expected return on assets	(232)	(244)	(464)	(489)
Amortization of:
Prior service cost	0	0	0	0
Unrecognized net loss (gain)	24	27	47	54
Net periodic benefit cost (income)	(24)	(36)	(49)	(72)
Pension Benefits | American Airlines, Inc.
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	0	1	1
Interest cost	182	180	364	360
Expected return on assets	(231)	(243)	(460)	(487)
Amortization of:
Prior service cost	0	0	0	0
Unrecognized net loss (gain)	24	27	47	54
Net periodic benefit cost (income)	(24)	(36)	(48)	(72)
Retiree Medical and Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	6	8	12	16
Interest cost	18	17	35	34
Expected return on assets	(2)	(2)	(5)	(5)
Amortization of:
Prior service cost	4	3	9	7
Unrecognized net loss (gain)	(6)	(6)	(11)	(13)
Net periodic benefit cost (income)	20	20	40	39
Retiree Medical and Other Postretirement Benefits | American Airlines, Inc.
Defined Benefit Plan Disclosure [Line Items]
Service cost	6	8	12	16
Interest cost	18	17	35	34
Expected return on assets	(2)	(2)	(5)	(5)
Amortization of:
Prior service cost	4	3	9	7
Unrecognized net loss (gain)	(6)	(6)	(11)	(13)
Net periodic benefit cost (income)	$ 20	$ 20	$ 40	$ 39