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Summary of Significant Accounting Policies - Concentrations of Risk (Details)	12 Months Ended
	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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