Debt Obligations - Additional Information (Details) - USD ($) shares in Millions					3 Months Ended		6 Months Ended	9 Months Ended
	Apr. 01, 2020	Jan. 03, 2018	Oct. 07, 2017	Oct. 05, 2017	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 14, 2020	Oct. 02, 2020
Line of Credit Facility [Line Items]
Long-term debt					$ 315,517,000			$ 315,517,000		$ 290,055,000
Facility expiration period								1 year
Unamortized debt issuance expense					3,834,000			$ 3,834,000		4,995,000
Amortization of debt issuance costs					700,000	$ 100,000		2,100,000	$ 500,000
Debt issuance costs								900,000	500,000
Interest expense					300,000	$ 200,000		700,000	$ 800,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit					0		$ 10,000,000	0		1,533,000
Interest rate above prime rate							0.25%
Matures date							Jun. 15, 2022
Unamortized debt issuance expense					12,000			12,000		25,000
2018 TAB Payments
Line of Credit Facility [Line Items]
Debt Instruments discounted fair value	$ 10,000,000.0
Notes payable gross fair value					31,700,000			31,700,000		31,700,000
Preferred share	3.3
TAB payment contribution	$ 16,800,000
Other Options | Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit					0			0		1,500,000
Senior Secured Credit Facility
Line of Credit Facility [Line Items]
Notes payable maturity date							Oct. 07, 2022
Amount of term loan credit facility			$ 130,000,000.0
Unamortized debt issuance expense					3,800,000			3,800,000		5,000,000.0
Senior Secured Credit Facility | Line of Credit
Line of Credit Facility [Line Items]
Line of credit			$ 5,000,000
Senior Secured Credit Facility | Term Loan
Line of Credit Facility [Line Items]
Aggregate on the term loan in tranches			Jul. 31, 2019
Debt instrument, Interest rate, Stated percentage			6.00%
Debt instrument, Interest rate terms			Interest is calculated upon each tranche at LIBOR for either one, two, three, or six months, as selected by Holdco, plus an applicable margin of 6.00% per annum.
Debt instrument, Term			5 years
Long-term debt					286,800,000			286,800,000		261,700,000
Line of credit			$ 125,000		35,000,000.0			35,000,000.0			$ 68,000,000.0	$ 91,400,000
Principal contractually repaid rate			0.75%
Senior Secured Credit Facility | Term Loan | Maximum
Line of Credit Facility [Line Items]
Amount of term loan credit facility			$ 125,000,000
RCP 2 | 2017 Seller Note
Line of Credit Facility [Line Items]
Notes payable				$ 81,300,000
Notes payable maturity date				Jan. 15, 2025
Debt Instruments discounted fair value				$ 78,700,000
Notes payable gross fair value					$ 6,400			$ 6,400		$ 6,400
RCP 3 | 2018 Seller Note
Line of Credit Facility [Line Items]
Notes payable		$ 22,100,000
Notes payable maturity date		Jan. 15, 2025
Debt Instruments discounted fair value		$ 21,200,000
Notes payable gross fair value		$ 3,000,000.0
RCP 3 | 2018 TAB Payments
Line of Credit Facility [Line Items]
Notes payable maturity date		Apr. 15, 2037
Debt Instruments discounted fair value		$ 28,900,000
Amortized tax benefit		$ 48,400,000
Annual installments starting date		Apr. 15, 2023