Employee Benefit Plans - Components of Net Periodic Benefit Cost (Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1	$ 1	$ 1	$ 1
Interest cost	176	169	352	338
Expected return on assets	(204)	(226)	(406)	(452)
Amortization of:
Prior service cost (benefit)	7	7	14	14
Unrecognized net loss (gain)	38	36	76	72
Net periodic benefit cost (income)	18	(13)	37	(27)
Retiree Medical and Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	2	2
Interest cost	8	9	17	17
Expected return on assets	(4)	(6)	(8)	(11)
Amortization of:
Prior service cost (benefit)	(59)	(59)	(118)	(119)
Unrecognized net loss (gain)	(8)	(5)	(16)	(10)
Net periodic benefit cost (income)	(62)	(60)	(123)	(121)
American Airlines, Inc. [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	1	1
Interest cost	175	168	350	336
Expected return on assets	(203)	(225)	(405)	(450)
Amortization of:
Prior service cost (benefit)	7	7	14	14
Unrecognized net loss (gain)	38	36	76	72
Net periodic benefit cost (income)	18	(13)	36	(27)
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	8	9	17	17
Expected return on assets	(4)	(6)	(8)	(11)
Amortization of:
Prior service cost (benefit)	(59)	(59)	(118)	(119)
Unrecognized net loss (gain)	(8)	(5)	(16)	(10)
Net periodic benefit cost (income)	$ (62)	$ (60)	$ (123)	$ (121)