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Escrow Deposit Per Aircraft

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

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Fair Value Measurements - Narrative (Details) $ in Thousands		3 Months Ended			4 Months Ended	9 Months Ended		14 Months Ended
	Oct. 29, 2024 aircraft	Dec. 31, 2024 USD ($)	Mar. 31, 2024 USD ($)	Sep. 30, 2023 USD ($)	Feb. 28, 2025 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2025 USD ($)	Jul. 02, 2024 USD ($)	Dec. 31, 2023	Apr. 30, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Restricted cash									$ 200,000
Derivative liability			$ 8,204			$ 8,200
A320 and A321 \| Forecast
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Number of aircraft to be sold \| aircraft	23
Total purchase price								$ 519,000
Escrow deposit per aircraft					$ 50,000
Increase in net liquidity from sale								$ 225,000
Impairment loss		$ 285,000
Collateral Pledged
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Restricted cash									$ 50,000
8.00% Senior Secured Notes Due 2025 \| Secured Debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate percentage				8.00%		8.00%	8.00%			8.00%
1.00% convertible notes due 2026 \| Convertible Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Stated interest rate percentage						1.00%				1.00%	1.00%
1.00% convertible notes due 2026 \| Convertible Notes \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Favorable mark to market adjustments, derivative liability			$ 500	$ 5,900			$ 18,400
Credit Card Processing Agreement \| Collateral Pledged
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Restricted cash						$ 50,000
Control Agreements For Interest And Fee Payments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Restricted cash						44,400
Corporate credit cards \| Collateral Pledged
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Restricted cash						6,000
Standby Letters of Credit \| Secured Debt
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Letters of credit, limit, amount						69,600
Restricted cash						69,700
Letter of credit facility, amount outstanding						$ 56,300