Debt Covenant, Appraisal Ratio of Aircraft Collateral

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- Definition

Debt Covenant, Debt Default, Trigger Amount for ERISA Event Liabilities

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- Definition

Debt Covenant, Debt Default, Trigger Amount for Impairments of Collateral

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- Definition

Debt Covenant, Debt Default, Trigger Amount for Judgments

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- Definition

Debt Covenant, Minimum Fixed Charge Ratio at Test Period End

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- Definition

Debt Covenant, Minimum Unrestricted Cash Requirement at Any Determination Date

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No definition available.

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- Definition

Debt Covenant, Secured Leverage Ratio, at Test Period End

+ References

No definition available.

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- Definition

Debt Covenant, Unrestricted Cash Requirement at the End of Each Calendar Month

+ References

No definition available.

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- Definition

Number of Aircraft Securing Debt Agreement

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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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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- Definition

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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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

The cash inflow from a long-term borrowing made from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth. Alternate caption: Proceeds from Advances from Affiliates.

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- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt - Additional Information (Detail)			2 Months Ended	3 Months Ended			9 Months Ended	12 Months Ended	13 Months Ended	14 Months Ended	19 Months Ended
Debt - Additional Information (Detail)	Mar. 13, 2019 USD ($) Aircraft	Sep. 28, 2018 USD ($)	Mar. 13, 2023	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Sep. 30, 2021	Dec. 30, 2022	Mar. 31, 2020	Mar. 13, 2023	Sep. 30, 2020	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Mar. 17, 2014 USD ($)
Debt Instrument [Line Items]
Letters of credit outstanding under the facility												$ 19,800,000	$ 19,600,000
Principal												$ 630,000,000	617,500,000
5.25% Senior Notes due March 15, 2019 [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Interest rate on Senior Notes												5.25%		5.25%
Debt issued														$ 500,000,000.0
Principal												$ 500,000,000	500,000,000
6% Related Party Term Loan [Member] \| Medium-term Notes [Member]
Debt Instrument [Line Items]
Interest rate on Senior Notes												6.00%
Debt issued		$ 130,000,000
Proceeds from Related Party Debt		130,000,000
Principal												$ 130,000,000
Letter of Credit to Secure workers Compensation Policies, Air Medical License, and a Traditional Provider Contract [Member]
Debt Instrument [Line Items]
Letters of credit outstanding under the facility												12,100,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Letters of credit outstanding under the facility												7,700,000
Repayments of Lines of Credit		$ 122,700,000
Principal												$ 0	$ 117,500,000
Subsequent Event [Member] \| Medium-term Notes [Member]
Debt Instrument [Line Items]
Debt issued	$ 70,000,000
Principal	$ 70,000,000
Number of aircraft securing debt agreement \| Aircraft	91
Debt covenant, minimum unrestricted cash requirement at the end of each calendar month	$ 20,000,000
Debt covenant, minimum cash and cash equivalents held solly by the Company and guarantors	$ 10,000,000
Debt covenant, appraisal ratio of aircraft collateral at quarter end	4.00
Event of default, judgments (in excess of)	$ 2,500,000
Event of default, ERISA event liabilities (in excess of)	2,500,000
Event of default, impairments of collateral (in excess of)	$ 2,500,000
LIBOR [Member] \| Subsequent Event [Member] \| Medium-term Notes [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	6.00%
Base Rate [Member] \| Subsequent Event [Member] \| Medium-term Notes [Member]
Debt Instrument [Line Items]
Basis spread on variable rate (percent)	5.00%
Scenario, Forecast [Member] \| Medium-term Notes [Member]
Debt Instrument [Line Items]
Debt covenant, minimum fixed charge ratio at the end of each test period				0.9125	0.3750	0.1875			0	1.2000
Debt covenant, secured leverage ratio, at test period end			3.75				4.25	4.00			4.50