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Significant Accounting Policies - Mutual Fund Administration Gross and Net Revenue (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenue from External Customer [Line Items]
Revenue	$ 39,014,433	$ 31,925,745
Administration revenue, gross
Revenue from External Customer [Line Items]
Revenue	6,926,414	5,592,658
Fund related expense
Revenue from External Customer [Line Items]
Expenses	4,466,157	3,827,249
Revenue, net of related expenses
Revenue from External Customer [Line Items]
Revenue	2,460,257	1,765,409
Broker Commission
Revenue from External Customer [Line Items]
Revenue	33,594	63,542
Expenses	48,521	60,886
Financing activity, net
Revenue from External Customer [Line Items]
Revenue	(14,927)	2,656
Mutual fund administration revenue, net
Revenue from External Customer [Line Items]
Revenue	$ 2,445,330	$ 1,768,065

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