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Investments - Summary of Market Value of Investments (Detail) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
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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Sum of the carrying amounts as of the balance sheet date of all investments.

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