Additional collateral coverage ratio.

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Calculated collateral coverage ratio.

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- Definition

Covenant capping restricted payments.

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- Definition

Debt instrument additional amount borrowed.

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Debt instrument amount borrowed.

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Line of credit, revolving commitments.

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No definition available.

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- Definition

Minimum collateral coverage ratio covenant.

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No definition available.

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- Definition

Rental coverage ratio.

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No definition available.

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- Definition

Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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Face (par) amount of debt instrument at time of issuance.

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- Definition

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of the required periodic payments of both interest and principal.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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Long-Term Debt, Finance Leases, and Other Borrowings - Additional Information (Detail)			1 Months Ended		3 Months Ended	9 Months Ended
	Dec. 27, 2022 USD ($)	Oct. 30, 2020 USD ($) $ / shares shares	Dec. 31, 2022	Dec. 31, 2021 USD ($)	Dec. 31, 2022	Jun. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2020 USD ($)	Apr. 09, 2020 $ / shares
Debt Instrument [Line Items]
Property and equipment-gross						$ 1,050,508,000	$ 1,270,563,000
Long-Term Debt						566,282,000	$ 599,735,000
Warrants of common stock exercise price \| $ / shares									$ 3.98
Treasury Loan [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Calculated collateral coverage ratio		1.6
Minimum collateral coverage ratio covenant			1.55
Treasury Loan [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Additional collateral coverage ratio		1.6
Loan Agreement [Member]
Debt Instrument [Line Items]
Warrants to purchase shares of common stock \| shares		4,899,497
Warrants of common stock exercise price \| $ / shares		$ 3.98
Spare Engine Facility [Member] \| Loan Agreement [Member]
Debt Instrument [Line Items]
Debt instrument, face amount				$ 35,300,000
Secured term loan facility, maximum borrowing capacity				$ 54,000,000.0
Debt instrument, maturity date				Dec. 31, 2027
Long term debt, fixed interest rate			7.50%		7.50%
United Capacity Purchase Agreement [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long term debt, basis spread on variable rate	3.50%
Revolving loan	$ 10,500,000
Covenant capping restricted payments	5,000,000.0
Revolving commitments	$ 30,700,000
Rental coverage ratio	1.00
United Capacity Purchase Agreement [Member] \| Revolving Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Amount required						15,000,000.0
United Capacity Purchase Agreement [Member] \| Revolving Credit Facility [Member] \| SOFR [Member]
Debt Instrument [Line Items]
Long term debt, basis spread on variable rate	4.50%
United Capacity Purchase Agreement [Member] \| United [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Amount funded by company						25,500,000
Equipment Notes [Member]
Debt Instrument [Line Items]
Long-Term Debt						120,100,000
Secured Term Loan Facility [Member] \| Loan Agreement [Member]
Debt Instrument [Line Items]
Secured term loan facility, maximum borrowing capacity		$ 200,000,000.0
Debt instrument, maturity date					Oct. 30, 2025
Secured Term Loan Facility [Member] \| Loan Agreement [Member] \| Treasury Loan [Member]
Debt Instrument [Line Items]
Long term debt, basis spread on variable rate		3.50%
Secured term loan facility, amount borrowed								$ 195,000,000.0
Secured term loan facility, additional amount borrowed						0
Debt instrument, maturity date		Oct. 30, 2025
Aircraft and Equipment [Member] \| Pledged as Collateral [Member]
Debt Instrument [Line Items]
Property and equipment-gross						$ 729,800,000