Accumulated Other Comprehensive Loss - Reclassifications out of AOCI (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications out of AOCI	$ (16)	$ (14)
Prior Service Benefit [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications out of AOCI	(40)	(33)
Actuarial Loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications out of AOCI	24	19
American Airlines, Inc. [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications out of AOCI	(16)	(14)
American Airlines, Inc. [Member] | Prior Service Benefit [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications out of AOCI	(40)	(33)
American Airlines, Inc. [Member] | Actuarial Loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassifications out of AOCI	$ 24	$ 19