Basis of Presentation and Summary of Significant Accounting Policies - Definite-Lived Intangible Assets (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Finite-Lived Intangible Assets [Line Items]
Accumulated amortization	$ (834)	$ (827)
Total	108	115
Domestic airport slots
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	365	365
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	300	300
Marketing agreements
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	$ 105	105
Useful life of intangible assets	30 years
Tradenames
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	$ 35	35
Airport gate leasehold rights
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	$ 137	137
Domestic airport slots and airport gate leasehold rights
Finite-Lived Intangible Assets [Line Items]
Useful life of intangible assets	25 years
American Airlines, Inc.
Finite-Lived Intangible Assets [Line Items]
Accumulated amortization	$ (834)	(827)
Total	108	115
American Airlines, Inc. | Domestic airport slots
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	365	365
American Airlines, Inc. | Customer relationships
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	300	300
American Airlines, Inc. | Marketing agreements
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	$ 105	105
Useful life of intangible assets	30 years
American Airlines, Inc. | Tradenames
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	$ 35	35
American Airlines, Inc. | Airport gate leasehold rights
Finite-Lived Intangible Assets [Line Items]
Amortizable intangible assets, gross	$ 137	$ 137
American Airlines, Inc. | Domestic airport slots and airport gate leasehold rights
Finite-Lived Intangible Assets [Line Items]
Useful life of intangible assets	25 years