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Compensation and Benefits - Restricted Share Activity and Class B Awards Activity (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | 4,634,924 |  |
Restricted Stock Awards and Restricted Stock Units |  |  |
Restricted share-based award compensation expense | $ 36,493 | $ 42,117 | $ 52,879
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value | $ 21,000 | $ 15,900 | $ 25,800
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation | 126,971 | 82,729 | 77,442
Taxes paid related to employee net share settlement | $ (4,530) | $ (2,078) | $ (2,564)
Unrecognized Tax Benefits, Income Tax Penalties Accrued | $ 200 | $ 300 |
Unvested restricted share-based awards |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Unvested at beginning of period | 5,005,422 | 4,678,457 | 4,013,986
Granted in Period, Number of Shares | 919,455 | 963,000 | 1,518,974
Forfeited in Period, Number of Shares | (43,091) | (17,289) | (67,255)
Vested in Period, Number of Shares | (588,144) | (618,746) | (787,248)
Unvested at end of period | 5,293,642 | 5,005,422 | 4,678,457
Weighted-Average Grant Date Fair Value |  |  |
Unvested at beginning of period (in dollars per share) | $ 35.00 | $ 38.04 | $ 38.79
Granted in Period, Weighted Average Grant Date Fair Value (in dollars per share) | 33.80 | 22.92 | 39.32
Forfeited in Period, Weighted Average Grant Date Fair Value (in dollars per share) | 30.92 | 34.61 | 36.09
Vested in Period, Weighted Average Grant Date Fair Value (in dollars per share) | 32.59 | 39.21 | 44.50
Unvested at end of period (in dollars per share) | $ 35.09 | $ 35.00 | $ 38.04
Restricted Stock Awards and Restricted Stock Units |  |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount | $ 76,400 |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition | 3 years 1 month 6 days |  |
Performance Shares |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Unvested at beginning of period | 0 |  |
Granted in Period, Number of Shares | 60,000 |  |
Forfeited in Period, Number of Shares | 0 |  |
Vested in Period, Number of Shares | 0 |  |
Unvested at end of period | 60,000 | 0 |
Weighted-Average Grant Date Fair Value |  |  |
Unvested at beginning of period (in dollars per share) | $ 0 |  |
Granted in Period, Weighted Average Grant Date Fair Value (in dollars per share) | 52.45 |  |
Forfeited in Period, Weighted Average Grant Date Fair Value (in dollars per share) | 0 |  |
Vested in Period, Weighted Average Grant Date Fair Value (in dollars per share) | 0 |  |
Unvested at end of period (in dollars per share) | $ 52.45 | $ 0 |
Restricted Stock Awards and Restricted Stock Units |  |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount | $ 2,300 |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition | 3 years 2 months 12 days |  |
General Partnership Units [Member] | Unvested restricted share-based awards |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Unvested at end of period | 5,183,747 |  |
Class A Common Stock |  |  |
Restricted Stock Awards and Restricted Stock Units |  |  |
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation | 126,971 | 82,729 | 77,442

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