Debt instrument additional amount borrowed.

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Debt instrument amount borrowed.

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Debt instrument, expiration month and year.

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Debt instrument imputed interest rate.

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- Definition

Debt Instrument Maturity Year

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- Definition

Number of aircraft financed.

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Number of aircraft refinanced.

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- Definition

Number of spare engines leased.

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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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Description of reference rate used for variable rate of debt instrument.

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- Definition

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.

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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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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount, after accumulated amortization, of debt discount.

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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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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

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Long-Term Debt, Finance Leases, and Other Borrowings - Schedule of Long-term Debt (Parenthetical) (Detail)		1 Months Ended					6 Months Ended	12 Months Ended
	Sep. 25, 2019 USD ($)	Dec. 31, 2021 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($) Airfleet	Jan. 31, 2019 USD ($)	Feb. 28, 2018 Engine	Mar. 31, 2022	Sep. 30, 2021	Sep. 30, 2016 USD ($) Air-craft	Sep. 30, 2015 USD ($) Air-craft	Nov. 14, 2020 USD ($)	Nov. 13, 2020 USD ($)	Oct. 31, 2020 USD ($)	Oct. 30, 2020 USD ($)
Senior and Subordinated Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2027 [Member]
Debt Instrument [Line Items]
Debt instrument maturity year							2027	2027
Senior and Subordinated Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2027 [Member] \| CRJ-900 [Member]
Debt Instrument [Line Items]
Number of aircraft financed \| Air-craft										7
Debt instrument, face amount										$ 170,200,000
Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2028 [Member]
Debt Instrument [Line Items]
Debt instrument maturity year							2028	2028
Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2028 [Member] \| Ten E-175 Aircraft [Member]
Debt Instrument [Line Items]
Number of aircraft financed \| Air-craft									10
Debt instrument, face amount									$ 246,000,000.0
Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2028 [Member] \| Ten E-175 Aircraft [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Long term debt interest rate percentage							4.75%
Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2028 [Member] \| Ten E-175 Aircraft [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Long term debt interest rate percentage							6.25%
Senior and Subordinated Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2028 [Member]
Debt Instrument [Line Items]
Debt instrument maturity year							2028	2028
Senior and Subordinated Notes Payable to Secured Parties, Collateralized by the Underlying Aircraft, Due 2028 [Member] \| Eight E-175 Aircraft [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, face amount									$ 195,300,000
Number of aircraft refinanced \| Air-craft									8
Other Obligations Due to Financial Institution, Collateralized by the Underlying Equipment, Due 2023 [Member]
Debt Instrument [Line Items]
Debt instrument maturity year							2023	2023
Imputed interest						9.128%
Number of spare engines leased \| Engine						2
Notes Payable to Financial Institution, Collateralized by the Underlying Equipment, Due 2024 [Member]
Debt Instrument [Line Items]
Debt instrument maturity year							2024	2024
Notes Payable to Financial Institution, Collateralized by the Underlying Equipment, Due 2024 [Member] \| Flight Equipment [Member]
Debt Instrument [Line Items]
Debt instrument, face amount					$ 91,200,000
Long term debt interest rate description							monthly LIBOR plus 3.10%
Notes Payable to Financial Institution, Collateralized by the Underlying Equipment, Due 2024 [Member] \| LIBOR [Member] \| Flight Equipment [Member]
Debt Instrument [Line Items]
Long term debt, basis spread on variable rate					3.10%
Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2023 [Member]
Debt Instrument [Line Items]
Debt instrument maturity year							2023	2023
Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2023 [Member] \| CRJ-700 Aircraft [Member]
Debt Instrument [Line Items]
Number of aircraft financed \| Airfleet				10
Debt instrument, face amount				$ 70,000,000.0
Long term debt interest rate description							monthly LIBOR plus 5.00%
Notes Payable to Financial Institution, Collateralized by the Underlying Aircraft, Due 2023 [Member] \| CRJ-700 Aircraft [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Long term debt, basis spread on variable rate				5.00%
Notes Payable to Financial Institution Due 2023 [Member]
Debt Instrument [Line Items]
Debt instrument maturity year							2023	2023
Notes Payable to Financial Institution Due 2023 [Member] \| Flight Equipment [Member]
Debt Instrument [Line Items]
Debt instrument, face amount			$ 8,000,000.0
Long term debt interest rate description							monthly LIBOR plus 5.00%
Notes Payable to Financial Institution Due 2023 [Member] \| LIBOR [Member] \| Flight Equipment [Member]
Debt Instrument [Line Items]
Long term debt, basis spread on variable rate							5.00%
Notes Payable to U.S Treasury Due 2025 [Member]
Debt Instrument [Line Items]
Debt instrument maturity year							2025	2025
Notes Payable to U.S Treasury Due 2025 [Member] \| Loan Agreement [Member]
Debt Instrument [Line Items]
Long term debt interest rate description							three-month LIBOR plus 3.50%
Long term debt, basis spread on variable rate							3.50%
Secured term loan facility, maximum borrowing capacity													$ 200,000,000.0
Secured term loan facility, amount borrowed														$ 43,000,000.0
Secured term loan facility, additional amount borrowed											$ 0	$ 152,000,000.0
Debt instrument, maturity date							Oct. 30, 2025
Notes Payable to Financial Institution, Collateralized by the Underlying Equipment, Due 2027 [Member]
Debt Instrument [Line Items]
Debt instrument maturity year							2027	2027
Debt instrument, face amount		$ 30,800,000
Long term debt interest rate description							monthly LIBOR plus 4.25%
Notes Payable to Financial Institution, Collateralized by the Underlying Equipment, Due 2027 [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Long term debt, basis spread on variable rate		4.25%
Senior Notes Due Two Thousand Twenty Seven [Member] \| CRJ-900 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount										$ 154,700,000
Long term debt interest rate description							monthly LIBOR plus 2.71%
Senior Notes Due Two Thousand Twenty Seven [Member] \| CRJ-900 [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Long term debt, basis spread on variable rate										2.71%
Subordinated Notes Due Two Thousand Twenty Seven [Member] \| CRJ-900 [Member]
Debt Instrument [Line Items]
Imputed interest										6.25%
Debt discount										$ 8,100,000
Senior Notes Due 2008 [Member] \| Eight E-175 Aircraft [Member]
Debt Instrument [Line Items]
Long term debt interest rate description							three-month LIBOR plus a spread ranging from 2.20% to 2.32%
Senior Notes Due 2008 [Member] \| Eight E-175 Aircraft [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, face amount									$ 172,000,000.0
Senior Notes Due 2008 [Member] \| Eight E-175 Aircraft [Member] \| LIBOR [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Long term debt, basis spread on variable rate									2.20%
Senior Notes Due 2008 [Member] \| Eight E-175 Aircraft [Member] \| LIBOR [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Long term debt, basis spread on variable rate									2.32%
Subordinated Notes Due 2008 [Member] \| Eight E-175 Aircraft [Member]
Debt Instrument [Line Items]
Long term debt interest rate percentage							4.50%
Working Capital Draw Loan [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 35,000,000.0		$ 35,000,000.0
Long term debt interest rate description							one-month LIBOR plus 3.75%
Term loan, term	3 years		3 years
Debt instrument, expiration year and month	2022-09		2022-09
Working Capital Draw Loan [Member] \| LIBOR [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long term debt, basis spread on variable rate	3.75%		3.75%