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Term Loan and Credit Facility - Future Minimum Payments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jan. 01, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Less: unamortized issuance costs		$ (300)	$ (3,200)
Debt Instrument, Tranche One \| Medium-term Notes \| Term Facility
Debt Instrument [Line Items]
2021	$ 2,906
2022	11,625
2023	61,302
2024	102,260
Total minimum payments	178,093
Less: interest	(28,093)
Less: unamortized issuance costs	(1,943)
Less: current portion	0
Net carrying amount	$ 148,057