Stock-based Compensation - Stock Options Activity (Details) - Share-based Payment Arrangement, Option - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Shares
Balance at the beginning of the period (in shares)	50,000
Granted (in shares)	0
Exercised (in shares)	(50,000)
Forfeited/canceled (in shares)	0
Balance at the end of the period (in shares)	0	50,000
Exercise Price
Balance at the beginning of the period (in dollars per share)	$ 28.80
Granted (in dollars per share)	0
Exercised (in dollars per share)	28.80
Forfeited/canceled (in dollars per share)	0
Balance at the end of the period (in dollars per share)	$ 0	$ 28.80
Remaining Contractual Term (in years)
Remaining Contractual Term (in years)	0 years	3 months 25 days
Aggregate Intrinsic Value
Balance at the beginning of the period	$ 781
Exercised	993
Balance at the end of the period	$ 0	$ 781