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

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- Definition

Amount of the fee that accompanies borrowing money under the debt instrument.

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- Definition

The average effective interest rate during the reporting period.

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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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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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 carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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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 - Credit Agreement (Details) - USD ($)		3 Months Ended		9 Months Ended		12 Months Ended
Debt - Credit Agreement (Details) - USD ($)	Jun. 24, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Nov. 30, 2016
Debt Instrument [Line Items]
Principal payments on revolving credit facility				$ 27,690,000	$ 32,000,000	$ 32,000,000	$ 10,000,000	$ 0
Drawdown amounts				0	22,000,000	22,000,000	20,000,000	0
Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity								50,000,000
Borrowings outstanding under revolving line of credit facility		$ 0		0				27,700,000
Principal payments on revolving credit facility	$ 27,700,000				32,000,000	32,000,000.0	10,000,000.0	0
Drawdown amounts					22,000,000	22,000,000.0	20,000,000.0
Debt issuance costs		1,800,000		1,800,000					$ 1,700,000
Debt related commitment fee amount								100,000
Interest expense		$ 100,000	$ 400,000	$ 600,000	$ 1,300,000	$ 1,600,000	$ 1,600,000	$ 1,700,000
Revolving Credit Facility \| Weighted Average Interest Rate
Debt Instrument [Line Items]
Interest rate during the period						3.02%	4.95%	4.88%
Revolving Credit Facility \| Effective Interest Rate
Debt Instrument [Line Items]
Interest rate during the period						3.93%	6.48%	6.10%
Senior Term Loan
Debt Instrument [Line Items]
Debt instrument, face amount									$ 50,000,000