Employee Benefit Plans - Components of Net Periodic Benefit Cost (Income) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1	$ 1	$ 2	$ 2
Interest cost	175	169	527	507
Expected return on assets	(204)	(226)	(611)	(678)
Amortization of:
Prior service cost (benefit)	7	7	21	21
Unrecognized net loss (gain)	37	36	113	108
Net periodic benefit cost (income)	16	(13)	52	(40)
Retiree Medical and Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	3	3
Interest cost	9	9	26	26
Expected return on assets	(4)	(6)	(12)	(17)
Amortization of:
Prior service cost (benefit)	(59)	(59)	(177)	(178)
Unrecognized net loss (gain)	(8)	(5)	(24)	(15)
Net periodic benefit cost (income)	(61)	(60)	(184)	(181)
American Airlines, Inc. [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	2	2
Interest cost	174	168	524	504
Expected return on assets	(203)	(225)	(609)	(675)
Amortization of:
Prior service cost (benefit)	7	7	21	21
Unrecognized net loss (gain)	37	35	113	107
Net periodic benefit cost (income)	16	(14)	51	(41)
American Airlines, Inc. [Member] | Retiree Medical and Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	3	3
Interest cost	9	9	26	26
Expected return on assets	(4)	(6)	(12)	(17)
Amortization of:
Prior service cost (benefit)	(59)	(59)	(177)	(178)
Unrecognized net loss (gain)	(8)	(5)	(24)	(15)
Net periodic benefit cost (income)	$ (61)	$ (60)	$ (184)	$ (181)