Summary of Significant Accounting Policies - Property and Equipment (Details) - USD ($) $ in Thousands	2 Months Ended	10 Months Ended	12 Months Ended
	Mar. 12, 2025	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Property, Plant and Equipment [Line Items]
Depreciation	$ 27,457	$ 105,158	$ 177,872	$ 218,106
Amortization of capitalized software	6,322	28,646	33,879	22,998
Total depreciation and amortization	54,853	$ 190,244	325,273	320,872
Aircraft, engines and flight simulators
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications		25 years
Spare rotables and flight assemblies | Maximum
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications		25 years
Spare rotables and flight assemblies | Minimum
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications		7 years
Other equipment and vehicles | Maximum
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications		7 years
Other equipment and vehicles | Minimum
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications		5 years
Internal use software | Maximum
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications		10 years
Internal use software | Minimum
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications		3 years
Buildings
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications		40 years
Heavy maintenance and major overhaul
Property, Plant and Equipment [Line Items]
Amortization of heavy maintenance	$ 21,074	$ 56,440	$ 113,522	$ 79,768