Fair Value Measurements (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed-income securities owned	$ 31,040	$ 32,148
Assets, fair value	154,603	166,715
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	10,826	10,900
Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed-income securities owned	31,040	32,148
Assets, fair value	137,005	149,449
Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	10,826	10,900
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	10,826	10,900
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	105,965	117,301
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	105,965	117,301
Investment Funds sponsored by LSV
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment funds sponsored by LSV	$ 6,772	$ 6,366

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
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 35
-Paragraph 54B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482134/820-10-35-54B

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
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-Section 50
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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
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 320
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 45
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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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