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v3.25.1

Long-Term Debt, Finance Leases, and Other Borrowings - Additional Information (Detail) |  |  |  |  |  | 2 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Nov. 23, 2024 | Jan. 11, 2024 USD ($) | Sep. 06, 2023 USD ($) | Dec. 27, 2022 USD ($) | Oct. 30, 2020 USD ($) $ / shares shares | Nov. 22, 2024 | Sep. 30, 2024 USD ($) $ / shares | Jul. 16, 2024 USD ($) | Sep. 30, 2023 USD ($) | Nov. 14, 2020 USD ($) | Nov. 13, 2020 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Property and equipment, net |  |  |  |  |  |  | $ 426,351,000 |  | $ 698,022,000 |  |
Long-Term Debt |  |  |  |  |  |  | 310,271,000 |  | 528,278,000 |  |
Debt outstanding |  |  |  |  |  |  | $ 315,210,000 |  | $ 538,274,000 |  |
Warrants of common stock exercise price | $ / shares |  |  |  |  |  |  | $ 3.98 |  |  |  |
Principal payments |  |  |  |  |  |  | $ 23,300,000 |  |  |  |
Treasury Loan [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Debt outstanding |  |  |  |  |  |  | 113,700,000 |  |  |  |
Principal payments |  |  |  |  |  |  | 25,400,000 |  |  |  |
Treasury Loan [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Minimum collateral coverage ratio covenant | 1.55 |  |  |  |  | 1.44 |  |  |  |  |
Treasury Loan [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Calculated collateral coverage ratio |  |  |  |  | 1.55 |  |  |  |  |  |
Treasury Loan [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Additional collateral coverage ratio |  |  |  |  | 1.55 |  |  |  |  |  |
Loan Agreement [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Secured term loan facility, amount borrowed |  |  |  |  | $ 43,000,000 |  |  |  |  |  |
Secured term loan facility, additional amount borrowed |  |  |  |  |  |  |  |  |  |  | $ 152,000,000
Warrants to purchase shares of common stock | shares |  |  |  |  | 4,899,497 |  |  |  |  |  |
Warrants of common stock exercise price | $ / shares |  |  |  |  | $ 3.98 |  |  |  |  |  |
Debt issuance costs allocated to warrants |  |  |  |  |  |  | 100,000 |  |  |  |
Loan Agreement [Member] | EDC Loans [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Debt issuance costs |  |  |  |  |  |  |  |  |  |  | 3,100,000
Loan Agreement [Member] | FortyThreeMillionTreasuryLoanMember |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Capitalized debt issuance costs, net |  |  |  |  | $ 700,000 |  |  |  |  |  |
Loan Agreement [Member] | $152M Treasury Loan [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Capitalized debt issuance costs, net |  |  |  |  |  |  |  |  |  |  | 2,300,000
Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Repayments of long term debt |  | $ 2,100,000 |  |  |  |  |  |  |  |  |
Permitted amount to redraw from existing credit facility |  |  | $ 7,900,000 |  |  |  |  |  |  |  |
Revolving Credit Facility [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revolving commitments |  |  | 50,700,000 |  |  |  |  |  |  |  |
Revolving Credit Facility [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Revolving commitments |  |  | $ 30,700,000 |  |  |  |  |  |  |  |
Equipment Notes [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Long-Term Debt |  |  |  |  |  |  | $ 85,500,000 |  |  |  |
Secured Term Loan Facility [Member] | Loan Agreement [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Secured term loan facility, maximum borrowing capacity |  |  |  |  | 200,000,000 |  |  |  |  |  |
Secured Term Loan Facility [Member] | Loan Agreement [Member] | Treasury Loan [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Secured term loan facility, amount borrowed |  |  |  |  | $ 43,000,000 |  |  |  |  |  |
Secured term loan facility, additional amount borrowed |  |  |  |  |  |  |  |  |  | $ 0 | $ 152,000,000
Debt instrument, maturity date |  |  |  |  | Oct. 30, 2025 |  |  |  |  |  |
Long term debt, basis spread on variable rate |  |  |  |  | 3.50% |  |  |  |  |  |
United Capacity Purchase Agreement [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Repayments of long term debt |  | $ 10,500,000 |  |  |  |  |  |  |  |  |
Minimum liquidity requirement of cash and cash equivalents |  |  |  |  |  |  |  | $ 15,000,000 |  |  |
United Capacity Purchase Agreement [Member] | United [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Percentage of controllable completion factor |  |  |  |  |  |  | 99.30% |  |  |  |
United Capacity Purchase Agreement [Member] | Revolving Credit Facility [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Repayments of lines of credit |  |  |  |  |  |  | $ 10,500,000 |  |  |  |
Long term debt, basis spread on variable rate |  |  | 3.50% | 3.50% |  |  |  |  |  |  |
Revolving loan |  |  |  | $ 10,500,000 |  |  |  |  |  |  |
Revolving commitments |  |  |  | 30,700,000 |  |  |  |  |  |  |
Covenant capping restricted payments |  |  |  | $ 5,000,000 |  |  |  |  |  |  |
Rental coverage ratio |  |  |  | 1 |  |  |  |  |  |  |
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% | 4.50% |  |  |  |  |  |  |
United Capacity Purchase Agreement [Member] | Revolving Credit Facility [Member] | United [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Amount funded by company |  |  |  |  |  |  | 25,500,000 |  |  |  |
Additional prepayment with potential forgiveness |  |  |  |  |  |  | 15,000,000 |  |  |  |
Deemed prepayment, outstanding |  |  |  |  |  |  | 4,500,000 |  |  |  |
United Capacity Purchase Agreement [Member] | Revolving Credit Facility [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Amount required |  |  |  | $ 15,000,000 |  |  |  |  |  |  |
Aircraft and Equipment [Member] | Pledged as Collateral [Member] |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |
Property and equipment, net |  |  |  |  |  |  | $ 438,400,000 |  |  |  |

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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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- Definition Amount of decrease in line of credit facility from forgiveness by the holder of the line of credit. + References No definition available. + Details
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- Definition Fair value of the amount outstanding under the credit facility. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-10 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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- Definition Amount of the required periodic payments of both interest and principal. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(19)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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- Definition Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 835 -SubTopic 30 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482949/835-30-55-8 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 69B -Publisher FASB -URI https://asc.fasb.org/1943274/2147481568/470-20-55-69B Reference 5: http://www.xbrl.org/2003/role/exampleRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 69C -Publisher FASB -URI https://asc.fasb.org/1943274/2147481568/470-20-55-69C Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1D -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-1D Reference 7: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-4 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(f)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-14 + Details
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- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 50 -Paragraph 1 -SubTopic 10 -Topic 360 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 7A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 852 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481372/852-10-55-10 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(8)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 360 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478451/942-360-50-1 + Details
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