Debt and Other Obligations - Narrative (Details)				3 Months Ended			9 Months Ended
	Oct. 15, 2024 USD ($)	Apr. 30, 2021 USD ($) day $ / shares shares	May 12, 2020 USD ($) day	Sep. 30, 2024 USD ($) $ / shares shares	Mar. 31, 2024 USD ($) aircraftLeasebackTransaction aircraft	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) $ / shares shares	Sep. 30, 2023 USD ($)	Dec. 31, 2023 USD ($)
Debt Instrument [Line Items]
Derivative liability					$ 8,204,000		$ 8,200,000
Total				$ 1,986,400,000			1,986,400,000		$ 3,054,800,000
Less unamortized discounts, net				47,600,000			47,600,000		69,000,000.0
Repayments of long-term debt				31,900,000		$ 45,200,000	151,500,000	$ 287,000,000.0
Gain on extinguishment of debt				0		$ 0	14,996,000	$ 0
Current maturities of long-term debt, net, and finance leases				$ 1,253,376,000			$ 1,253,376,000		315,580,000
Aircraft Leaseback Transaction
Debt Instrument [Line Items]
Number of sale-leaseback transactions | aircraftLeasebackTransaction					5
Number of aircraft on leases | aircraftLeasebackTransaction					2
Failed aircraft sale leaseback | aircraftLeasebackTransaction					3
Current maturities of long-term debt, net, and finance leases					$ 123,500,000
Fixed Rate Loans
Debt Instrument [Line Items]
Extinguishment of debt					$ 139,600,000
Sale leaseback transaction, number of aircraft related to loans | aircraft					5
Gain on extinguishment of debt					$ 15,000,000
Convertible notes due 2025 | Convertible Notes
Debt Instrument [Line Items]
Principal amount			$ 175,000,000
Convertible debt, conversion price threshold			130.00%
Number of trading days required for conversion price threshold | day			20
Number of consecutive days required for trading days for conversion price threshold | day			30
Number of consecutive business days for conversion price threshold | day			5
Number of consecutive trading days measurement period | day			5
Trading price threshold per principal amount portion			98.00%
Shares conversion rate per portion of principal amount (in shares) | shares				97.5929			97.5929
Principal amount portion for trading price threshold			$ 1,000	$ 1,000			$ 1,000
Conversion price (in dollars per share) | $ / shares				$ 10.25			$ 10.25
1.00% convertible notes due 2026 | Convertible Notes
Debt Instrument [Line Items]
Principal amount		$ 500,000,000.0
Convertible debt, conversion price threshold		130.00%
Number of trading days required for conversion price threshold | day		20
Number of consecutive days required for trading days for conversion price threshold | day		30
Number of consecutive business days for conversion price threshold | day		5
Trading price threshold per principal amount portion		98.00%
Shares conversion rate per portion of principal amount (in shares) | shares		20.3791		25.3578			25.3578
Principal amount portion for trading price threshold		$ 1,000		$ 1,000			$ 1,000
Conversion price (in dollars per share) | $ / shares		$ 49.07		$ 39.44			$ 39.44
Number of trading days before maturity redemption allowed | day		40
Total				$ 481,300,000			$ 481,300,000
Less unamortized discounts, net				18,700,000			18,700,000
Revolving credit facilities | Revolving credit facility due in 2026 | Line of Credit
Debt Instrument [Line Items]
Line of credit facility, remaining borrowing capacity				$ 300,000,000			$ 300,000,000		$ 300,000,000
Revolving credit facilities | Revolving credit facility due in 2026 | Line of Credit | Subsequent Event
Debt Instrument [Line Items]
Proceeds from lines of credit	$ 300,000,000