Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Amortizable Intangible Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Accumulated amortization	$ (622)	$ (578)
Total	320	364
American Airlines, Inc. [Member]
Finite-Lived Intangible Assets [Line Items]
Accumulated amortization	(622)	(578)
Total	320	364
Domestic Airport Slots [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	365	365
Domestic Airport Slots [Member] | American Airlines, Inc. [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	365	365
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	300	300
Customer Relationships [Member] | American Airlines, Inc. [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	300	300
Marketing Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	105	105
Marketing Agreements [Member] | American Airlines, Inc. [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	105	105
Tradenames [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	35	35
Tradenames [Member] | American Airlines, Inc. [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	35	35
Airport Gate Leasehold Rights [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	137	137
Airport Gate Leasehold Rights [Member] | American Airlines, Inc. [Member]
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	$ 137	$ 137