Employee Benefit Plans - Components of Net Periodic Benefit Cost (Income) (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Pension Benefits [Member]
Components of net periodic benefit cost:
Service cost	$ 1	$ 1	$ 2	$ 2
Interest cost	180	187	541	562
Expected return on assets	(198)	(188)	(592)	(562)
Prior service cost (benefit)	7	7	21	21
Unrecognized net loss (gain)	36	32	108	95
Net periodic benefit cost (income)	26	39	80	118
Pension Benefits [Member] | American Airlines, Inc. [Member]
Components of net periodic benefit cost:
Service cost	0	0	1	1
Interest cost	179	186	538	559
Expected return on assets	(197)	(187)	(589)	(560)
Prior service cost (benefit)	7	7	21	21
Unrecognized net loss (gain)	36	32	108	94
Net periodic benefit cost (income)	25	38	79	115
Retiree Medical And Other Postretirement Benefits [Member]
Components of net periodic benefit cost:
Service cost	1	1	3	2
Interest cost	10	12	29	36
Expected return on assets	(5)	(5)	(16)	(15)
Prior service cost (benefit)	(59)	(60)	(178)	(180)
Unrecognized net loss (gain)	(6)	(4)	(17)	(12)
Net periodic benefit cost (income)	(59)	(56)	(179)	(169)
Retiree Medical And Other Postretirement Benefits [Member] | American Airlines, Inc. [Member]
Components of net periodic benefit cost:
Service cost	1	1	3	2
Interest cost	10	12	29	36
Expected return on assets	(5)	(5)	(16)	(15)
Prior service cost (benefit)	(59)	(60)	(178)	(180)
Unrecognized net loss (gain)	(6)	(4)	(17)	(12)
Net periodic benefit cost (income)	$ (59)	$ (56)	$ (179)	$ (169)