Debt Obligations - Schedule of Debt Obligations (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Line of Credit Facility [Line Items]
Gross notes payable to sellers	$ 41,064		$ 41,064
Less debt discount	(8,548)		(9,205)
Notes payable to sellers, net	32,516		31,859
Gross credit and guaranty facility	286,847		261,683
Debt issuance costs	(3,834)		(4,995)
Credit and guaranty facility, net	283,013		256,688
Total debt obligations	315,517		290,055
Revolving Credit Facility
Line of Credit Facility [Line Items]
Gross revolving credit facility state tax credits	0	$ 10,000	1,533
Revolving credit facility state tax credits, net	(12)		1,508
Debt issuance costs	$ (12)		$ (25)

Credit and guaranty facility, net

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Gross notes payable to sellers

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Notes payable to sellers, net

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Revolving credit facility state tax credits, net

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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.

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Amount, after accumulated amortization, of debt discount.

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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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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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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