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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
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Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized | 14,000,000 |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period | 5 years |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant | 5,601,288 |  |
Number of Awards |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value | $ 15,900 | $ 25,800 | $ 19,800
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount | $ 82,000 |  |
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition | 3 years 2 months 12 days |  |
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation | 82,729 | 77,442 | 48,646
Taxes paid related to employee net share settlement | $ (2,078) | $ (2,564) | $ (1,477)
Unvested restricted share-based awards |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |
Unvested at beginning of period | 4,678,457 | 4,013,986 | 3,394,910
Granted in Period, Number of Shares | 963,000 | 1,518,974 | 1,268,500
Forfeited in Period, Number of Shares | (17,289) | (67,255) | (3,628)
Vested in Period, Number of Shares | (618,746) | (787,248) | (645,796)
Unvested at end of period | 5,005,422 | 4,678,457 | 4,013,986
Weighted-Average Grant Date Fair Value |  |  |
Unvested at beginning of period (in dollars per share) | $ 38.04 | $ 38.79 | $ 44.47
Granted in Period, Weighted Average Grant Date Fair Value (in dollars per share) | 22.92 | 39.32 | 28.30
Forfeited in Period, Weighted Average Grant Date Fair Value (in dollars per share) | 34.61 | 36.09 | 39.56
Vested in Period, Weighted Average Grant Date Fair Value (in dollars per share) | 39.21 | 44.50 | 48.06
Unvested at end of period (in dollars per share) | $ 35.00 | $ 38.04 | $ 38.79
Number of Awards |  |  |
Restricted share-based award compensation expense | $ 42,117 | $ 52,879 | $ 49,142
Class B Liability Awards |  |  |
Number of Awards |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period | 5 years |  |
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 | 4,898,297 |  |
Class A Common Stock |  |  |
Number of Awards |  |  |
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation | 82,729 | 77,442 | 48,646

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- Definition Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(3) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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