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Compensation and Benefits - Additional information (Details) - USD ($) $ in Thousands | 9 Months Ended |
--- | --- | ---
Sep. 30, 2020 | Sep. 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 | $ 88,000 |  |
Recognition period | 3 years 3 months 18 days |  |
Shares paid for tax withholding for share based compensation (in shares) | 126,971 |  |
Taxes paid related to employee net share settlement | $ (4,530) | $ (2,078) |
2020 Grant |  |  |
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 |  |

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