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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- Definition

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

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- Definition

Debt Instrument, Number Of Series Issued

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- Definition

Notes issues at price as percentage of par.

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- Definition

Number Of Assets Used To Secure Debt

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Debt Obligations - Narrative (Details) $ in Millions	1 Months Ended
Debt Obligations - Narrative (Details) $ in Millions	May 31, 2021	Sep. 30, 2021 airframe	May 31, 2021	May 31, 2021 airframe	May 31, 2021 USD ($)	May 31, 2021 debtSeries	May 31, 2021 engine
Long Term Debt
Number of debt series issued \| debtSeries						3
Number of assets used to secure debt \| engine							2
WEST VI
Long Term Debt
Number of assets used to secure debt				1			29
WEST VI Notes \| WEST VI
Long Term Debt
Debt instrument, face amount					$ 336.7
WEST VI Series A Notes
Long Term Debt
Number of assets used to secure debt \| airframe		1
Fixed rate (as a percent)		3.10%	3.104%
Debt instrument, term	8 years
Notes issue price, percentage of par	99.99481%
WEST VI Series A Notes \| WEST VI
Long Term Debt
Debt instrument, face amount					278.6
WEST VI Series B Notes
Long Term Debt
Number of assets used to secure debt \| airframe		1
Fixed rate (as a percent)		5.44%	5.438%
Debt instrument, term	8 years
Notes issue price, percentage of par	99.99996%
WEST VI Series B Notes \| WEST VI
Long Term Debt
Debt instrument, face amount					38.7
WEST VI Series C Notes
Long Term Debt
Number of assets used to secure debt \| airframe		1
Fixed rate (as a percent)		7.39%	7.385%
Debt instrument, term	8 years
Notes issue price, percentage of par	99.99869%
WEST VI Series C Notes \| WEST VI
Long Term Debt
Debt instrument, face amount					$ 19.4