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Investments - Summary of Market Value of Investments (Detail) - USD ($) | Mar. 31, 2021 | Dec. 31, 2020
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Investment Holdings [Line Items] |  |
Total Investments | $ 142,695,192 | $ 128,401,136
Securities held in Consolidated Funds |  |
Investment Holdings [Line Items] |  |
Fair value investments | 47,164,927 | 33,233,307
Securities held in Consolidated Funds | Parent |  |
Investment Holdings [Line Items] |  |
Fair value investments | 35,000,000.0 | 23,600,000
Securities held in Consolidated Funds | Redeemable Noncontrolling Interest |  |
Investment Holdings [Line Items] |  |
Fair value investments | 12,200,000 | 9,600,000
Company sponsored investments |  |
Investment Holdings [Line Items] |  |
Fair value investments | $ 95,530,265 | $ 95,167,829

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