Goodwill and Intangible Assets - Additional Information (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) Asset	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2017 USD ($)
Business Acquisition [Line Items]
Amortization expense	$ 380,000	$ 519,000	$ 1,141,000	$ 1,552,000	$ 2,070,000
Net intangible assets, end of year	$ 2,044,000		$ 2,044,000		$ 3,185,000
Number of infinite-lived intangible assets | Asset			1
Customer Relationships
Business Acquisition [Line Items]
Finite-lived intangibles acquired						$ 18,800,000
Acquired finite-lived intangible assets, useful life			8 years
Amortization expense			$ 1,100,000
Trade Names
Business Acquisition [Line Items]
Number of infinite-lived intangible assets | Asset			1
impairment of infinite-lived assets			$ 0