Tax Receivable Agreement (TRA) (Details) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended	12 Months Ended
	Feb. 28, 2018	Sep. 30, 2021	Dec. 31, 2020	Jul. 31, 2020
Tax Receivable Agreement
Tax savings payable to TRA Holders	85.00%	85.00%
Tax savings benefit recorded as APIC	15.00%
TRA payment		$ 9,700		$ 14,200
Tax benefit			$ 11,400
Total TRA liability		283,000
Current portion of liability related to tax receivable agreement		$ 10,976	$ 9,290