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Investments - Summary of Market Value of Investments (Detail) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Investment Holdings [Line Items]
Company sponsored equity method investments	$ 62,400,320	$ 61,149,774
Total Investments	116,433,476	139,437,178
Securities held in Consolidated Funds
Investment Holdings [Line Items]
Fair value investments	28,035,352	36,248,360
Securities held in Consolidated Funds | Parent
Investment Holdings [Line Items]
Fair value investments	19,900,000	21,100,000
Securities held in Consolidated Funds | Redeemable Noncontrolling Interest
Investment Holdings [Line Items]
Fair value investments	8,200,000	15,100,000
Company sponsored investments
Investment Holdings [Line Items]
Fair value investments	$ 25,997,804	$ 42,039,044

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Sum of the carrying amounts as of the balance sheet date of all investments.

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