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Share-Based Compensation - Additional Information (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Jan. 31, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reacquisition of share based compensation awards for tax-withholding purposes				$ 5,521	$ 4,099
Share-based compensation expense		$ 2,800	$ 3,400	8,700	$ 10,200
Unrecognized compensation cost		$ 8,800		$ 8,800
Unrecognized compensation cost, weighted-average period of recognition				1 year 3 months 18 days
Estimated fair value at vesting of share-based awards				$ 8,600
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Reacquisition of share based compensation awards for tax-withholding purposes	$ 5,500
Common Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining shares available for future issuance (in shares)		4,689,214		4,689,214