Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	$ 164,681	$ 143,126
Securities owned	31,174	29,583
Total assets measured at fair value	246,102	221,368
Contingent considerations	11,888	14,355
Total liabilities measured at fair value	11,888	14,355
Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities owned	0	0
Total assets measured at fair value	41,533	40,530
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities owned	31,174	29,583
Total assets measured at fair value	195,855	172,709
Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Contingent considerations	11,888	14,355
Total liabilities measured at fair value	11,888	14,355
NAV as a Practical Expedient
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets measured at fair value	8,714	8,129
Equity securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	41,533	40,530
Equity securities \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	41,533	40,530
Equity securities \| 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	164,681	143,126
Available-for-sale debt securities \| Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	0	0
Available-for-sale debt securities \| Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Available-for-sale securities	164,681	143,126
Investment funds sponsored by LSV
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment funds sponsored by LSV	8,148	8,129
Investment funds sponsored by LSV \| NAV as a Practical Expedient
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment funds sponsored by LSV	8,148	$ 8,129
Investments in limited partnership funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment funds sponsored by LSV	566
Investments in limited partnership funds \| NAV as a Practical Expedient
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment funds sponsored by LSV	$ 566

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.

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