Employee Benefit Plans - Components of Net Periodic Benefit Cost (Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1	$ 1	$ 1	$ 1
Interest cost	169	180	338	361
Expected return on assets	(226)	(197)	(452)	(394)
Amortization of:
Prior service cost (benefit)	7	7	14	14
Unrecognized net loss (gain)	36	36	72	72
Net periodic benefit cost (income)	(13)	27	(27)	54
Retiree Medical And Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	2	2
Interest cost	9	10	17	19
Expected return on assets	(6)	(5)	(11)	(10)
Amortization of:
Prior service cost (benefit)	(59)	(59)	(119)	(119)
Unrecognized net loss (gain)	(5)	(6)	(10)	(11)
Net periodic benefit cost (income)	(60)	(59)	(121)	(119)
American Airlines, Inc. [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	0	1	1
Interest cost	168	180	336	359
Expected return on assets	(225)	(196)	(450)	(393)
Amortization of:
Prior service cost (benefit)	7	7	14	14
Unrecognized net loss (gain)	36	36	72	72
Net periodic benefit cost (income)	(13)	27	(27)	53
American Airlines, Inc. [Member] | Retiree Medical And Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	2	2
Interest cost	9	10	17	19
Expected return on assets	(6)	(5)	(11)	(10)
Amortization of:
Prior service cost (benefit)	(59)	(59)	(119)	(119)
Unrecognized net loss (gain)	(5)	(6)	(10)	(11)
Net periodic benefit cost (income)	$ (60)	$ (59)	$ (121)	$ (119)