Stock-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for grant	8,481,554
Shares granted	3,029,949
Shares granted, weighted average grant date fair value	$ 11.15
Four Zero One K Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employer Discretionary Contribution Amount	$ 1,700	$ 1,600
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	3,029,949	2,387,645
Shares granted, weighted average grant date fair value	$ 11.15	$ 11.64
Compensation and benefits expense	$ 8,000	$ 7,800
Unrecognized compensation cost relating to unvested restricted stock	$ 77,600
Unrecognized compensation cost relating to unvested restricted stock, recognition period (in years)	3 years 7 months 6 days
Restricted Stock \| Share-based Payment Arrangement, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted, vesting period	1 year	1 year
Restricted Stock \| Share-based Payment Arrangement, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted, vesting period	5 years	5 years
Performance-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	307,479
Compensation and benefits expense	$ 586,000	$ 407,000
Unrecognized compensation cost relating to unvested restricted stock	$ 6,300
Unrecognized compensation cost relating to unvested restricted stock, recognition period (in years)	2 years 1 month 6 days

Amount, after tax, of expense for award under share-based payment arrangement.

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

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- Definition

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

+ 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 (i)
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- Definition

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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- Definition

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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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).

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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).

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- Definition

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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- Definition

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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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