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v3.25.4

Summary of Significant Accounting Policies - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Property, Plant and Equipment [Line Items] |  |  |
Depreciation | $ 91 | $ 71 | $ 50
Intangible amortization | 0 | 1 | 0
Total depreciation and amortization | 91 | 72 | $ 50
Property and equipment, net | $ 510 | 376 |
Aircraft and spare engines |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life | 25 years |  |
Residual Value | 10.00% |  |
Flight equipment leasehold improvements |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Residual Value | 0.00% |  |
Aircraft rotable parts |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Residual Value | 10.00% |  |
Ground property and equipment |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Residual Value | 0.00% |  |
Ground property and equipment | Minimum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life | 3 years |  |
Ground property and equipment | Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life | 10 years |  |
Ground equipment leasehold improvements |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Residual Value | 0.00% |  |
Ground equipment leasehold improvements | Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life | 10 years |  |
Internal-use software |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Residual Value | 0.00% |  |
Property and equipment, net | $ 23 | 18 |
Internal-use software | Minimum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life | 3 years |  |
Internal-use software | Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life | 10 years |  |
Capitalized maintenance |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Residual Value | 0.00% |  |
Property and equipment, net | $ 225 | $ 126 |
Buildings |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Residual Value | 10.00% |  |
Buildings | Maximum |  |  |
Property, Plant and Equipment [Line Items] |  |  |
Useful life | 40 years |  |

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