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Long-Term Debt, Finance Leases, and Other Borrowings - Additional Information (Detail)				1 Months Ended		12 Months Ended
	Nov. 13, 2020 USD ($)	Nov. 12, 2020 USD ($) Air-craft	Oct. 30, 2020 USD ($) $ / shares shares	Apr. 30, 2022	Dec. 31, 2021 USD ($)	Sep. 30, 2022 USD ($) $ / shares	Sep. 30, 2021 USD ($)	Nov. 14, 2020 USD ($)
Debt Instrument [Line Items]
Property and equipment, net						$ 865,254,000	$ 1,151,891,000
Long-Term Debt						599,735,000	651,410,000
Debt outstanding						$ 615,310,000	$ 670,335,000
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				1.5
Treasury Loan [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Additional collateral coverage ratio			1.6
Loan Agreement [Member]
Debt Instrument [Line Items]
Secured term loan facility, amount borrowed			$ 43,000,000.0
Secured term loan facility, additional amount borrowed	$ 152,000,000.0
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
Repayments of long term debt		$ 167,700,000
Number of aircraft financed \| Air-craft		44
Loan Agreement [Member] \| EDC Loans [Member]
Debt Instrument [Line Items]
Debt issuance costs	3,100,000
Repayments of long term debt	1,000,000.0
Payment of loans		$ 164,200,000
Discount for balance amount of loans		$ 3,500,000
Unamortized debt discounts	2,500,000
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
Spare Engine Facility [Member] \| Loan Agreement [Member]
Debt Instrument [Line Items]
Secured term loan facility, maximum borrowing capacity					$ 54,000.0
Long term debt, basis spread on variable rate					425.00%
Debt instrument, maturity date					Dec. 31, 2027
Debt instrument, face amount					$ 35,300
Long term debt interest rate description						LIBOR plus 4.25%
Long term debt, basis spread on variable rate					425.00%
Equipment Notes [Member]
Debt Instrument [Line Items]
Long-Term Debt						$ 131,000,000.0
Working Capital Draw Loan [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt outstanding						$ 15,600,000
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]
Secured term loan facility, amount borrowed			$ 43,000,000.0
Secured term loan facility, additional amount borrowed	$ 152,000,000.0							$ 0
Long term debt, basis spread on variable rate			3.50%
Debt instrument, maturity date			Oct. 30, 2025
Long term debt, basis spread on variable rate			3.50%
Aircraft and Equipment [Member] \| Pledged as Collateral [Member]
Debt Instrument [Line Items]
Property and equipment, net						$ 856,900,000