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Fair Value Measurements - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Unrealized (loss) gain on available-for-sale marketable securities, net of taxes	$ (1,014)	$ 703	$ (1,271)	$ 873	$ 1,656	$ (533)	$ (1,582)	$ 1,996
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Proceeds from available for sale municipal bonds							12,368	5,979
Realized loss								(100)
Realized gain							200
Net unrealized gains related to equity securities	(100)			3,200			4,000	4,200
Municipal bonds — available-for-sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Proceeds from available for sale municipal bonds	300			200			12,400	6,000
Realized loss	$ (100)			$ (100)				$ (100)
Realized gain							$ 200