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v3.25.4

Summary of Significant Accounting Policies - Concentrations of Risk (Details) | 12 Months Ended
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Dec. 31, 2025 vendor employeeGroup | Dec. 31, 2024 | Dec. 31, 2023
Concentration Risk [Line Items] |  |  |
Number of union-represented employee groups | employeeGroup | 7 |  |
Amount of employees represented by unions | 86.00% |  |
Number of vendors with pre-delivery deposits for flight equipment | vendor | 1 |  |
Cost Risk | Operating Expense | Aircraft Fuel Cost |  |  |
Concentration Risk [Line Items] |  |  |
Concentration risk | 24.00% | 28.00% | 31.00%

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