Basis of Presentation and Summary of Significant Accounting Policies - Significant Contract Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Disaggregation of Revenue [Line Items]
Contract balances, liability	$ 17,722	$ 16,813
Loyalty program liability
Disaggregation of Revenue [Line Items]
Contract balances, liability	10,564	10,054
Air traffic liability
Disaggregation of Revenue [Line Items]
Contract balances, liability	7,158	6,759
American Airlines, Inc.
Disaggregation of Revenue [Line Items]
Contract balances, liability	17,722	16,813
American Airlines, Inc. | Loyalty program liability
Disaggregation of Revenue [Line Items]
Contract balances, liability	10,564	10,054
American Airlines, Inc. | Air traffic liability
Disaggregation of Revenue [Line Items]
Contract balances, liability	$ 7,158	$ 6,759