Employee Incentive Plans - Summary of Unrecognized Gross Compensation Cost and Expected Period Over Which Remaining Gross Compensation Costs Will Be Recognized By Type of Award (Details) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($)
Restricted Stock And Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized Gross Compensation Costs	$ 9.7
Expected Period (in years) Over Which the Remaining Gross Compensation Costs Will Be Recognized	2 years 6 months
Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized Gross Compensation Costs	$ 6.5
Expected Period (in years) Over Which the Remaining Gross Compensation Costs Will Be Recognized	1 year 10 months 24 days

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

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)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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

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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