v3.24.0.1
Long-term Debt, Short-term Borrowings and Finance Lease Obligations - Senior Notes and General Debt (Details)
1 Months Ended 12 Months Ended
Mar. 31, 2021
USD ($)
day
$ / shares
Dec. 31, 2023
USD ($)
Dec. 31, 2022
USD ($)
Dec. 31, 2021
USD ($)
Debt Instrument [Line Items]        
Interest expense   $ 7,000,000 $ 7,000,000  
Debt issuance costs amortization   3,000,000 3,000,000  
Repayment of long-term debt   347,000,000 369,000,000 $ 1,892,000,000
Debt extinguishment expense   0 0 50,000,000
Pledged assets not separately reported flight equipment   7,100,000,000    
Interest paid, including capitalized interest, operating and investing activities   $ 80,000,000 $ 124,000,000 $ 180,000,000
Convertible Senior Notes Due 2026 | Senior Notes        
Debt Instrument [Line Items]        
Debt instrument, interest rate, stated percentage 0.50% 0.50%    
Debt instrument, face amount $ 750,000,000      
Proceeds from offering $ 734,000,000      
Debt instrument, convertible ratio (in dollars per share) | $ / shares $ 25.92      
Debt instrument, conversion ratio 0.0385802      
Convertible Senior Notes Due 2026 | Senior Notes | Debt Instrument, Redemption, Period One        
Debt Instrument [Line Items]        
Debt instrument, redemption price, percentage 100.00%      
Trading days | day 20      
Convertible Senior Notes Due 2026 | Senior Notes | Debt Instrument, Redemption, Period Two        
Debt Instrument [Line Items]        
Debt instrument, redemption price, percentage 130.00%      
Trading days | day 30