Employee Benefit Plans - Schedule of Changes in Projected Benefit Obligations (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2012
Reconciliation of benefit obligation:
Plan amendments				$ (1,900)
Pension Benefits [Member]
Reconciliation of benefit obligation:
Obligation beginning balance	$ 17,238	$ 16,395
Service cost	2	2	$ 2
Interest cost	721	749	737
Actuarial (gain) loss	1,016	729
Plan amendments	0	0
Settlements	(4)	(2)
Benefit payments	(726)	(635)
Other	28	0
Obligation end of period	18,275	17,238	16,395
Retiree Medical And Other Postretirement Benefits [Member]
Reconciliation of benefit obligation:
Obligation beginning balance	991	1,131
Service cost	4	3	3
Interest cost	39	47	50
Actuarial (gain) loss	49	(105)
Plan amendments	0	7
Settlements	0	0
Benefit payments	(80)	(92)
Other	8	0
Obligation end of period	1,011	991	1,131
American Airlines, Inc. [Member]
Reconciliation of benefit obligation:
Plan amendments				$ (1,900)
American Airlines, Inc. [Member] | Pension Benefits [Member]
Reconciliation of benefit obligation:
Obligation beginning balance	17,148	16,310
Service cost	2	2	1
Interest cost	717	746	733
Actuarial (gain) loss	1,007	725
Plan amendments	0	0
Settlements	(4)	(2)
Benefit payments	(723)	(633)
Other	28	0
Obligation end of period	18,175	17,148	16,310
American Airlines, Inc. [Member] | Retiree Medical And Other Postretirement Benefits [Member]
Reconciliation of benefit obligation:
Obligation beginning balance	990	1,129
Service cost	4	3	3
Interest cost	39	47	50
Actuarial (gain) loss	49	(104)
Plan amendments	0	7
Settlements	0	0
Benefit payments	(80)	(92)
Other	8	0
Obligation end of period	$ 1,010	$ 990	$ 1,129