Compensation and Benefits - Restricted Share Activity and Class B Awards Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
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

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

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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).

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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.

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Number of shares authorized for issuance under share-based payment arrangement.

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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