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Investment Portfolio - Narrative (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Total Investment portfolio	$ 212,389,477	$ 138,476,022
New consolidations of Company sponsored investments	16,444,640
Securities held in Consolidated Funds
Fair value investments	153,499,790	65,890,500
Parent | Securities held in Consolidated Funds
Fair value investments	85,900,000	42,600,000
Redeemable Noncontrolling Interest | Securities held in Consolidated Funds
Fair value investments	$ 67,600,000	$ 23,300,000

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The amount of the increase during the period of a noncontrolling interest resulting from the parent's increase in control and consolidation of the entity in which one or more outside parties had a noncontrolling interest.

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
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Sum of the carrying amounts as of the balance sheet date of all investments.

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