Employee Benefit Plans - Schedule of Accumulated Benefit Obligations Exceeding Fair Value of Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 8,820	$ 13,349
Fair value of plan assets	8,221	12,254
Accumulated benefit obligation/Accumulated postretirement benefit obligation	8,814	13,341
Fair value of plan assets	8,221	12,254
Retiree Medical and  Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation/Accumulated postretirement benefit obligation	1,259	1,308
Fair value of plan assets	118	128
American Airlines, Inc. | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	8,807	13,258
Accumulated benefit obligation/Accumulated postretirement benefit obligation	8,801	13,251
Fair value of plan assets	8,209	12,175
American Airlines, Inc. | Retiree Medical and  Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation/Accumulated postretirement benefit obligation	1,258	1,307
Fair value of plan assets	$ 118	$ 128