v3.26.3
Long-term Debt, Short-term Borrowings and Finance Lease Obligations - Finance Lease Obligations (Details) - USD ($)
$ in Millions
Sep. 30, 2026
Apr. 01, 2026
Dec. 31, 2025
Debt Instrument [Line Items]      
Long-term debt $ 8,393   $ 8,498
Finance lease, liability 421   449
Total debt and finance lease obligations 8,450   8,560
Less: Debt issuance costs (57)   (62)
Less: Current maturities (482)   (769)
Long-term debt and finance lease obligations 7,911   7,729
Fixed rate special facility bonds, due through 2036      
Debt Instrument [Line Items]      
Secured debt 43   43
2019-1 Series AA, due through 2032      
Debt Instrument [Line Items]      
Secured debt 409   424
2019-1 Series A, due through 2028      
Debt Instrument [Line Items]      
Secured debt 128   132
2019-1 Series B, due through 2027      
Debt Instrument [Line Items]      
Secured debt 38   45
2020-1 Series A, due through 2032      
Debt Instrument [Line Items]      
Secured debt 407   428
2020-1 Series B, due through 2028      
Debt Instrument [Line Items]      
Secured debt 73   82
Fixed rate equipment notes, due through 2036      
Debt Instrument [Line Items]      
Secured debt 573   127
Floating rate equipment notes, due through 2036      
Debt Instrument [Line Items]      
Secured debt 619   673
Aircraft failed sale-leaseback transactions, due through 2036      
Debt Instrument [Line Items]      
Secured debt 2,011   2,103
TrueBlue® senior secured notes, due through 2031      
Debt Instrument [Line Items]      
Long-term debt 1,991   1,990
TrueBlue® senior secured term loan facility, due through 2029      
Debt Instrument [Line Items]      
Long-term debt 742   744
Unsecured CARES Act Payroll Support Program loan, due through 2030      
Debt Instrument [Line Items]      
Unsecured debt 259   259
Unsecured Consolidated Appropriations Act Payroll Support Program Extension loan, due through 2031      
Debt Instrument [Line Items]      
Unsecured debt 144   144
Unsecured American Rescue Plan Act of 2021 Payroll Support loan, due through 2031      
Debt Instrument [Line Items]      
Unsecured debt 132   132
0.50% convertible senior notes, due through 2026      
Debt Instrument [Line Items]      
Long-term debt $ 0 $ 0 $ 325
Debt instrument, interest rate, stated percentage (in percent) 0.50% 0.50% 0.50%
2.50% convertible senior notes, due through 2029      
Debt Instrument [Line Items]      
Long-term debt $ 460   $ 460
Debt instrument, interest rate, stated percentage (in percent) 2.50%   2.50%