Commitments and Contingencies - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) aircraft	Dec. 31, 2022 USD ($)	Aug. 07, 2022 hangar aircraft	Dec. 31, 2021 USD ($) subsidiary	Apr. 30, 2021 USD ($)	Feb. 28, 2021 USD ($)
Other Commitments [Line Items]
Number of airline subsidiaries | subsidiary				2
Government grant awarded | $				$ 75.8	$ 40.0	$ 37.4
Government grant awarded, increase | $						$ 5.6
Right-of-use asset obtained in exchange for operating lease liability | $	$ 8.5	$ 34.7
Operating lease, weighted average discount rate, percent	4.00%	3.20%
Operating lease, weighted average remaining lease, term (in years)	3 years 10 months 24 days	4 years 3 months 18 days
Operating lease, payments | $	$ 26.0	$ 23.5
Contractual obligation | $	546.1
Contractual obligation, to be paid, year one | $	205.7
Number of aircrafts			3
Loss contingency, receivable | $	$ 0.1	$ 1.0
Number of aircraft hangars | hangar			1
Property Leases | Minimum
Other Commitments [Line Items]
Lessee, operating lease, term of contract	1 month
Property Leases | Maximum
Other Commitments [Line Items]
Lessee, operating lease, term of contract	9 years
Equipment Leases | Minimum
Other Commitments [Line Items]
Lessee, operating lease, term of contract	1 month
Equipment Leases | Maximum
Other Commitments [Line Items]
Lessee, operating lease, term of contract	5 years
Aircraft Provided By Customers
Other Commitments [Line Items]
Lessee, number of leased aircraft	16
Aircraft Leased From External Customers
Other Commitments [Line Items]
Lessee, number of leased aircraft	4
B-767-300
Other Commitments [Line Items]
Number of owned aircrafts	14
Number of aircrafts to be purchased	6
A-321-200
Other Commitments [Line Items]
Number of owned aircrafts	6
A-330-200
Other Commitments [Line Items]
Number of aircrafts to be purchased	7
A330-300
Other Commitments [Line Items]
Number of owned aircrafts	3