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Fair Value Measurements (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fixed-income securities owned | $ 32,748 | $ 32,148
Assets, fair value | 159,148 | 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 | 10,626 | 10,900
Significant Other Observable Inputs (Level 2) |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Fixed-income securities owned | 32,748 | 32,148
Assets, fair value | 141,684 | 149,449
Equity securities |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Available-for-sale securities | 10,626 | 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 | 10,626 | 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 | 108,936 | 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 | 108,936 | 117,301
Investment Funds sponsored by LSV |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Investment funds sponsored by LSV | $ 6,838 | $ 6,366

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- Definition 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. + References 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 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6A -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-6A + Details
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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 -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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- Definition 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 -Subparagraph (aa) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481800/320-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 320 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481830/320-10-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 30 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479130/326-30-45-1 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 940 -SubTopic 320 -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481961/940-320-45-2 + Details
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