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

No definition available.

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Balance Type:	na
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- Definition

Face (par) amount of debt instrument at time of issuance.

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+ Details

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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.

+ References

No definition available.

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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.

+ References

No definition available.

+ Details

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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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.

+ Details

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- Definition

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 cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Debt - Additional Information (Details) - USD ($)				3 Months Ended		9 Months Ended
Debt - Additional Information (Details) - USD ($)	Mar. 24, 2020	Nov. 18, 2019	May 03, 2019	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Debt Instrument [Line Items]
Letters of credit outstanding				$ 30,800,000		$ 30,800,000		$ 30,900,000
Term Loan A Facility
Debt Instrument [Line Items]
Interest expense				500,000	$ 600,000	1,600,000	$ 2,000,000.0
Term Loan A Facility \| Morgan Stanley Senior Funding, Inc \| Credit Agreement
Debt Instrument [Line Items]
Debt instrument term, years			4 years
Debt instrument, aggregate principal amount			$ 100,000,000.0
Amount borrowed under debt facility		$ 100,000,000.0
Term Loan A Facility \| Morgan Stanley Senior Funding, Inc \| Credit Agreement \| Adjusted One-Month LIBOR
Debt Instrument [Line Items]
Debt instrument, applicable margin on variable rate		1.75%
Revolving Credit Facility \| Morgan Stanley Senior Funding, Inc \| Credit Agreement
Debt Instrument [Line Items]
Debt instrument term, years			4 years
Maximum borrowing capacity			$ 100,000,000.0
Letters of credit outstanding				$ 30,800,000		$ 30,800,000		$ 30,800,000
Revolving Credit Facility \| Morgan Stanley Senior Funding, Inc \| Credit Agreement \| Adjusted One-Month LIBOR
Debt Instrument [Line Items]
Debt instrument, applicable margin on variable rate	1.75%