Employee Benefit Plans - Components of Net Periodic Benefit Cost (Income) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1	$ 0
Interest cost	183	181
Expected return on assets	(232)	(244)
Amortization of:
Prior service cost	0	0
Unrecognized net loss (gain)	24	27
Net periodic benefit cost (income)	(24)	(36)
Pension Benefits | American Airlines, Inc.
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	0
Interest cost	182	180
Expected return on assets	(231)	(243)
Amortization of:
Prior service cost	0	0
Unrecognized net loss (gain)	24	27
Net periodic benefit cost (income)	(24)	(36)
Retiree Medical and Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	6	8
Interest cost	18	17
Expected return on assets	(2)	(2)
Amortization of:
Prior service cost	4	3
Unrecognized net loss (gain)	(6)	(6)
Net periodic benefit cost (income)	20	20
Retiree Medical and Other Postretirement Benefits | American Airlines, Inc.
Defined Benefit Plan Disclosure [Line Items]
Service cost	6	8
Interest cost	18	17
Expected return on assets	(2)	(2)
Amortization of:
Prior service cost	4	3
Unrecognized net loss (gain)	(6)	(6)
Net periodic benefit cost (income)	$ 20	$ 20