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

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

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Amount of cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement.

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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.

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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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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).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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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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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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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Amount of statutory penalties accrued for a tax position claimed or expected to be claimed by the entity, in its tax return.

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