Employee Benefit Plans - Schedule of Changes in Projected Benefit Obligations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Pension Benefits [Member]
Reconciliation of benefit obligation:
Benefit obligation at beginning of period	$ 18,275	$ 17,238
Service cost	3	2	$ 2
Interest cost	674	721	749
Actuarial (gain) loss	(1,910)	1,016
Settlements	(4)	(4)
Benefit payments	(662)	(726)
Other	2	28
Benefit obligation at end of period	16,378	18,275	17,238
Retiree Medical And Other Postretirement Benefits [Member]
Reconciliation of benefit obligation:
Benefit obligation at beginning of period	1,011	991
Service cost	5	4	3
Interest cost	35	39	47
Actuarial (gain) loss	(133)	49
Settlements	0	0
Benefit payments	(81)	(80)
Other	0	8
Benefit obligation at end of period	837	1,011	991
American Airlines, Inc. [Member] | Pension Benefits [Member]
Reconciliation of benefit obligation:
Benefit obligation at beginning of period	18,175	17,148
Service cost	2	2	2
Interest cost	670	717	746
Actuarial (gain) loss	(1,905)	1,007
Settlements	(4)	(4)
Benefit payments	(659)	(723)
Other	3	28
Benefit obligation at end of period	16,282	18,175	17,148
American Airlines, Inc. [Member] | Retiree Medical And Other Postretirement Benefits [Member]
Reconciliation of benefit obligation:
Benefit obligation at beginning of period	1,010	990
Service cost	5	4	3
Interest cost	35	39	47
Actuarial (gain) loss	(132)	49
Settlements	0	0
Benefit payments	(81)	(80)
Other	0	8
Benefit obligation at end of period	$ 837	$ 1,010	$ 990