Fair Value Measurements (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed-income securities owned	$ 26,174	$ 34,064
Assets, fair value	163,145	145,649
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed-income securities owned	0	0
Assets, fair value	12,731	12,142
Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed-income securities owned	26,174	34,064
Assets, fair value	143,482	127,341
Fair Value Measured at Net Asset Value Per Share
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment funds sponsored by LSV	6,932	6,166
Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	12,731	12,142
Equity securities \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	12,731	12,142
Equity securities \| Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	0	0
Available-for-sale debt securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	117,308	93,277
Available-for-sale debt securities \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	0	0
Available-for-sale debt securities \| Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	$ 117,308	$ 93,277

Fair value of investment other than investment in equity security, investment in debt security and equity method investment. Includes, but is not limited to, investment in certain entities that calculate net asset value per share. Example includes, but is not limited to, investment in hedge fund, venture capital fund, private equity fund, and real estate partnership or fund.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
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-Publisher FASB
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- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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-Publisher FASB
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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The fair value as of the balance sheet date of firm holdings in debt obligations issued by the US government including short-term Treasury bills, medium-term Treasury notes, and long-term Treasury bonds, as well as debt issued by agencies. Includes both pledged (to counterparties as collateral for financing transactions) and unpledged holdings.

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