v3.26.3
Investments (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Dec. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]          
Other investments $ 117   $ 117   $ 146
Impairment of equity investments 78 $ 0 78 $ 0  
American Airlines, Inc.          
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]          
Other investments 117   117   146
Impairment of equity investments 78 $ 0 78 $ 0  
Equity Securities          
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]          
Total 408   408   603
Equity Securities | American Airlines, Inc.          
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]          
Total $ 408   $ 408   $ 603
China Southern Airlines          
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]          
Ownership interest, fair value method investments 1.50%   1.50%   1.50%
Carrying value, fair value method investments $ 104   $ 104   $ 203
China Southern Airlines | American Airlines, Inc.          
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]          
Ownership interest, fair value method investments 1.50%   1.50%   1.50%
Carrying value, fair value method investments $ 104   $ 104   $ 203
Republic Airways Holdings, Inc.          
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]          
Ownership interest, equity method investments 20.80%   20.80%   20.80%
Carrying value, equity method investments $ 187   $ 187   $ 254
Impairment of equity investments $ 78        
Republic Airways Holdings, Inc. | American Airlines, Inc.          
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]          
Ownership interest, equity method investments 20.80%   20.80%   20.80%
Carrying value, equity method investments $ 187   $ 187   $ 254
Impairment of equity investments $ 78