Investments - Summary of Market Value of Investments (Detail) - USD ($)	Jun. 30, 2020	Dec. 31, 2019
Investment Holdings [Line Items]
Company sponsored equity method investments	$ 60,915,291	$ 61,149,774
Total Investments	114,348,626	139,437,178
Securities held in Consolidated Funds
Investment Holdings [Line Items]
Fair value investments	29,262,767	36,248,360
Securities held in Consolidated Funds \| Parent
Investment Holdings [Line Items]
Fair value investments	18,800,000	21,100,000
Securities held in Consolidated Funds \| Redeemable Noncontrolling Interest
Investment Holdings [Line Items]
Fair value investments	10,500,000	15,100,000
Company sponsored investments
Investment Holdings [Line Items]
Fair value investments	$ 24,170,568	$ 42,039,044

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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