Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Compensation and Benefits - Additional information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)	14,000,000
Number of shares available for grant (in shares)	4,631,934
Unrecognized compensation expense	$ 97,100
Recognition period	3 years 4 months 24 days
Shares paid for tax withholding for share based compensation (in shares)	126,971
Taxes paid related to employee net share settlement	$ (4,530)	$ (1,824)
2020 Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 34,100
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted - Number of awards (in shares)	919,455
Requisite service period	5 years
Unvested - Number of awards (in shares)	5,296,632		5,005,422
Restricted Stock Units RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted - Number of awards (in shares)	3,370
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted - Number of awards (in shares)	60,000
Requisite service period	3 years
Shares issued in period (in shares)	60,000
Unvested - Number of awards (in shares)	60,000		0
Performance Shares \| Potential Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested - Number of awards (in shares)	90,000