Summary of Significant Accounting Policies - Property and Equipment (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) aircraft_engine aircraft flightSimulator	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Property, Plant and Equipment [Line Items]
Number of spare engines capitalized | aircraft_engine	20
Number of flight simulators capitalized | flightSimulator	1
Depreciation, Depletion and Amortization, Nonproduction [Abstract]
Depreciation	$ 193,079	$ 179,470	$ 155,326
Amortization of capitalized software	12,203	10,191	6,574
Total depreciation and amortization	$ 297,211	278,588	225,264
Spare engines
Property, Plant and Equipment [Line Items]
Number of aircraft under operating lease | aircraft_engine	12
A320 Family | Aircraft
Property, Plant and Equipment [Line Items]
Number of aircraft under operating lease | aircraft	67
Minimum | Aircraft
Property, Plant and Equipment [Line Items]
Operating leases, term	8 years
Maximum | Aircraft
Property, Plant and Equipment [Line Items]
Operating leases, term	18 years
Aircrafts, Major Spare Rotable Parts, Avionics, and Assemblies
Property, Plant and Equipment [Line Items]
Residual value, percentage	10.00%
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 | Minimum
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications	7 years
Spare rotables and flight assemblies | Maximum
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications	25 years
Other equipment and vehicles | Minimum
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications	5 years
Other equipment and vehicles | Maximum
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications	7 years
Internal use software
Depreciation, Depletion and Amortization, Nonproduction [Abstract]
Capitalized computer software, net	$ 32,600	24,300
Capitalized software costs during the year	$ 20,500	21,500	5,900
Internal use software | Minimum
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications	3 years
Internal use software | Maximum
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications	10 years
Buildings
Property, Plant and Equipment [Line Items]
Depreciable lives used for the principal depreciable asset classifications	30 years
Aircraft | A320 Family
Property, Plant and Equipment [Line Items]
Number of aircraft capitalized | aircraft	106
Aircraft | Minimum
Property, Plant and Equipment [Line Items]
Finance lease contract term	8 years
Aircraft | Maximum
Property, Plant and Equipment [Line Items]
Finance lease contract term	18 years
Spare engines | Minimum
Property, Plant and Equipment [Line Items]
Operating leases, term	6 months
Spare engines | Maximum
Property, Plant and Equipment [Line Items]
Operating leases, term	18 years
Heavy maintenance and major overhaul
Depreciation, Depletion and Amortization, Nonproduction [Abstract]
Amortization of heavy maintenance	$ 91,929	$ 88,927	$ 63,364