Employee Benefit Plans - Components of Net Periodic Benefit Cost (Income) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 1	$ 1	$ 2
Interest cost	180	188	542	568
Expected return on assets	(245)	(230)	(733)	(690)
Amortization of:
Prior service cost (benefit)	0	4	0	18
Unrecognized net loss (gain)	26	25	79	80
Net periodic benefit cost (income)	(39)	(12)	(111)	(22)
Pension Benefits | American Airlines, Inc.
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	1	1
Interest cost	178	187	539	564
Expected return on assets	(243)	(228)	(729)	(685)
Amortization of:
Prior service cost (benefit)	0	4	0	18
Unrecognized net loss (gain)	26	25	79	80
Net periodic benefit cost (income)	(39)	(12)	(110)	(22)
Retiree Medical and Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	8	4	23	10
Interest cost	17	12	51	36
Expected return on assets	(2)	(2)	(7)	(7)
Amortization of:
Prior service cost (benefit)	3	(3)	11	(10)
Unrecognized net loss (gain)	(6)	(10)	(19)	(27)
Net periodic benefit cost (income)	20	1	59	2
Retiree Medical and Other Postretirement Benefits | American Airlines, Inc.
Defined Benefit Plan Disclosure [Line Items]
Service cost	8	4	23	10
Interest cost	17	12	51	36
Expected return on assets	(2)	(2)	(7)	(7)
Amortization of:
Prior service cost (benefit)	3	(3)	11	(10)
Unrecognized net loss (gain)	(6)	(10)	(19)	(27)
Net periodic benefit cost (income)	$ 20	$ 1	$ 59	$ 2