Long-Term Debt, Finance Leases, and Other Borrowings - Additional Information (Detail)							1 Months Ended	3 Months Ended		6 Months Ended		9 Months Ended
	Mar. 18, 2025	Dec. 23, 2024	Jul. 01, 2024 USD ($)	Sep. 06, 2023 USD ($)	Dec. 27, 2022 USD ($)	Oct. 30, 2020 USD ($) $ / shares shares	Dec. 31, 2015 USD ($)	Mar. 31, 2025 USD ($) $ / shares	Mar. 31, 2024 USD ($)	Mar. 31, 2025 USD ($) $ / shares	Mar. 31, 2024 USD ($)	Jun. 30, 2023 USD ($)	Sep. 30, 2024 USD ($)	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Property and equipment-gross								$ 75,247,000		$ 75,247,000			$ 600,924,000
Long-Term Debt								130,255,000		130,255,000			310,271,000
Current portion of long-term debt								$ 98,603,000		$ 98,603,000			$ 50,455,000
Gain on investments									$ 7,230,000		$ 7,230,000
Warrants of common stock exercise price | $ / shares								$ 3.98		$ 3.98
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]
Warrants to purchase shares of common stock | shares						4,899,497
Warrants of common stock exercise price | $ / shares						$ 3.98
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
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
United Capacity Purchase Agreement [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long term debt, basis spread on variable rate				3.50%	3.50%
Revolving loan					$ 10,500,000
Covenant capping restricted payments					5,000,000
Repayments of lines of credit								$ 10,500,000
Revolving commitments					$ 30,700,000
Rental coverage ratio					1
United Capacity Purchase Agreement [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Amount required												$ 15,000,000
Fee waiver granted on minimum liquidity requirement			$ 15,000,000
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] | United [Member]
Debt Instrument [Line Items]
Percentage of controllable completion factor										99.30%
United Capacity Purchase Agreement [Member] | United [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Deemed prepayment, outstanding								4,500,000		$ 4,500,000
Amount funded by company												$ 25,500,000
Additional prepayment with potential forgiveness								$ 15,000,000		$ 15,000,000
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%
Percentage of all in rate								8.06%		8.06%
Secured term loan facility, amount borrowed														$ 195,000,000.0
Secured term loan facility, additional amount borrowed								$ 0		$ 0
Debt instrument, maturity date						Oct. 30, 2025
UST Loan [Member] | Minimum [Member]
Debt Instrument [Line Items]
Minimum Collateral Coverage Ratio 1	91	99
E175 Aircraft [Member]
Debt Instrument [Line Items]
Remaining Balance							$ 73,400,000
Aircraft and Equipment [Member] | Pledged as Collateral [Member]
Debt Instrument [Line Items]
Property and equipment-gross								$ 60,400,000		$ 60,400,000