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v3.25.4

Commitments and Contingencies - Additional Information (Details) $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Jul. 31, 2025 aircraft | Jun. 30, 2025 USD ($) | Dec. 31, 2025 USD ($) aircraft employeeGroup | Dec. 31, 2024 USD ($)
Long-term Purchase Commitment [Line Items] |  |  |  |
Number of aircraft to be outfitted with engines | aircraft | 91 |  |  |
Amount awarded from other party |  |  |  | $ 40
Number of union-represented employee groups | employeeGroup |  |  | 7 |
Amount of employees represented by unions |  |  | 86.00% |
Accrued liabilities for health care claims |  |  | $ 7 | 6
Internal Revenue Service (IRS) |  |  |  |
Long-term Purchase Commitment [Line Items] |  |  |  |
Preliminary assessment of estimated tax liability |  | $ 133 |  |
Other Assets |  |  |  |
Long-term Purchase Commitment [Line Items] |  |  |  |
Preproduction costs related to long-term supply arrangements, costs capitalized |  |  | 81 | 95
Other Noncurrent Liabilities |  |  |  |
Long-term Purchase Commitment [Line Items] |  |  |  |
Preproduction costs related to long-term supply arrangements, costs capitalized |  |  | $ 52 | $ 1
Total Aircraft |  |  |  |
Long-term Purchase Commitment [Line Items] |  |  |  |
Number of aircraft agreed to purchase | aircraft |  |  | 168 |
Total Aircraft | A320neo |  |  |  |
Long-term Purchase Commitment [Line Items] |  |  |  |
Number of aircraft agreed to purchase | aircraft |  |  | 20 |
Total Aircraft | A321neo |  |  |  |
Long-term Purchase Commitment [Line Items] |  |  |  |
Number of aircraft agreed to purchase | aircraft |  |  | 148 |

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