Employee Benefit Plans - Changes in Fair Value Measurements of Level 3 Investments (Details) - Level 3     - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Change in fair value measurements of level 3 investments
Fair value of plan assets at beginning of period	$ 68	$ 84
Relating to assets still held at the reporting date	(8)	(25)
Purchases	5	9
Sales	(2)	0
Fair value of plan assets at end of period	63	68
American Airlines, Inc.
Change in fair value measurements of level 3 investments
Fair value of plan assets at beginning of period	68	84
Relating to assets still held at the reporting date	(8)	(25)
Purchases	5	9
Sales	(2)	0
Fair value of plan assets at end of period	$ 63	$ 68