Debt and Other Obligations - Schedule of Interest Expense (Details) - USD ($) $ in Thousands	2 Months Ended	3 Months Ended		4 Months Ended	6 Months Ended
	Mar. 12, 2025	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Mar. 18, 2025
Debt Instrument [Line Items]
Commitment and other fees	$ 20	$ 492	$ 421	$ 605	$ 835
Amortization of deferred financing costs and fair value adjustments	1,004	12,633	3,487	13,026	7,069
Total	47,682	62,103	54,307	71,880	109,116
Accretion expense	0			0	2,105
Amortization of debt discount	0			109	5,767
Exit secured notes
Debt Instrument [Line Items]
Interest expense	0	$ 25,480	$ 0	30,800	0
DIP Term Loan
Debt Instrument [Line Items]
Interest expense	$ 6,869			$ 0	$ 0
Secured Debt | 8.00% Senior Secured Notes
Debt Instrument [Line Items]
Stated interest rate percentage	8.00%	8.00%	8.00%	8.00%	8.00%
Interest expense	$ 17,753	$ 0	$ 23,252	$ 0	$ 46,505
Accretion expense			1,100		2,100
Interest expense			22,200		44,400
Amortization of debt discount		100		100
Secured Debt | Exit secured notes
Debt Instrument [Line Items]
Stated interest rate percentage						92.50%
Fixed-rate term loans
Debt Instrument [Line Items]
Interest expense	13,175	11,847	17,503	14,764	35,355
Unsecured term loans | Unsecured term loans
Debt Instrument [Line Items]
Interest expense	265	1,528	346	1,599	685
Enhanced Equipment Trust Certificate | Class A 2015-1 EETC
Debt Instrument [Line Items]
Interest expense	1,879	2,281	2,505	2,784	5,117
Enhanced Equipment Trust Certificate | Class B 2015-1 EETC
Debt Instrument [Line Items]
Interest expense	0	0	5	0	446
Enhanced Equipment Trust Certificate | Class AA 2017-1 EETC
Debt Instrument [Line Items]
Interest expense	1,036	1,309	1,403	1,582	2,823
Enhanced Equipment Trust Certificate | Class A 2017-1 EETC
Debt Instrument [Line Items]
Interest expense	373	472	504	571	1,014
Enhanced Equipment Trust Certificate | Class B 2017-1 EETC
Debt Instrument [Line Items]
Interest expense	325	142	440	228	885
Enhanced Equipment Trust Certificate | Class B(R) 2025-1 EETC
Debt Instrument [Line Items]
Interest expense	0	5,913	0	5,913	0
Convertible notes
Debt Instrument [Line Items]
Convertible notes	1,246	0	4,432	0	8,363
Convertible notes | Convertible notes due 2026
Debt Instrument [Line Items]
Amortization of debt discount			4,400		8,900
Offset of favorable market-to-market adjustments					500
Revolving credit facility
Debt Instrument [Line Items]
Interest expense	3,732			0	0
Finance leases
Debt Instrument [Line Items]
Interest expense	$ 5	$ 6	$ 9	$ 8	$ 17