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Investment Portfolio - Narrative (Detail) - USD ($) | Mar. 31, 2019 | Dec. 31, 2018
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Total Investments | $ 164,791,720 | $ 203,488,217
Securities held in Consolidated Funds |  |
Fair value investments | 78,997,408 | 153,730,480
Parent | Securities held in Consolidated Funds |  |
Fair value investments | 48,800,000 | 84,700,000
Redeemable Noncontrolling Interest | Securities held in Consolidated Funds |  |
Fair value investments | $ 30,200,000 | $ 69,000,000

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