Amount of commitment made to pay deferred cash remuneration.

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- Definition

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

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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 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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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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No definition available.

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

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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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No definition available.

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Aggregate value of stock related to Restricted Stock Awards issued during the period.

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Compensation and Benefits - Additional information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
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)	3,878,720
Issuance of restricted stock awards	$ 0	$ 0
Shares paid for tax withholding for share based compensation (in shares)	176,194
2021 Grant
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of restricted stock awards	$ 44,200
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period (in years)	5 years
Granted - Number of awards (in shares)	741,555
Unvested - Number of awards (in shares)	5,251,822		5,293,642
Unrecognized compensation expense	$ 85,600
Recognition period (in years)	3 years 4 months 24 days
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted - Number of awards (in shares)	740,249
Restricted Stock Units RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted - Number of awards (in shares)	1,306
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period (in years)	3 years
Granted - Number of awards (in shares)	75,230
Unvested - Number of awards (in shares)	135,230		60,000
Unrecognized compensation expense	$ 5,800
Recognition period (in years)	3 years
Performance Shares \| Potential Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested - Number of awards (in shares)	165,233
Long-Term Cash Awards \| Deferred Bonus
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Awards granted, amount	$ 35,000