Employee Benefit Plans - Schedule of Changes in Fair Value of Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Pension Benefits [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of period	$ 11,395	$ 10,017
Actual return on plan assets	(1,151)	1,797
Employer contributions	475	286
Settlements	(4)	(4)
Benefit payments	(662)	(726)
Other	0	25
Fair value of plan assets at end of period	10,053	11,395
Funded status at end of period	(6,325)	(6,880)
Supplemental contributions by employer	433	261
Minimum required cash contribution	42	25
Retiree Medical And Other Postretirement Benefits [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of period	295	266
Actual return on plan assets	(24)	37
Employer contributions	35	72
Settlements	0	0
Benefit payments	(81)	(80)
Other	0	0
Fair value of plan assets at end of period	225	295
Funded status at end of period	(612)	(716)
American Airlines, Inc. [Member] | Pension Benefits [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of period	11,340	9,968
Actual return on plan assets	(1,148)	1,788
Employer contributions	472	286
Settlements	(4)	(4)
Benefit payments	(659)	(723)
Other	0	25
Fair value of plan assets at end of period	10,001	11,340
Funded status at end of period	(6,281)	(6,835)
Supplemental contributions by employer	433	261
Minimum required cash contribution	39	25
American Airlines, Inc. [Member] | Retiree Medical And Other Postretirement Benefits [Member]
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of period	295	266
Actual return on plan assets	(24)	37
Employer contributions	35	72
Settlements	0	0
Benefit payments	(81)	(80)
Other	0	0
Fair value of plan assets at end of period	225	295
Funded status at end of period	$ (612)	$ (715)