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Significant Accounting Policies - Mutual Fund Administration Gross and Net Revenue (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenue from External Customer [Line Items]
Revenue	$ 31,925,745	$ 32,579,373
Administration revenue, gross
Revenue from External Customer [Line Items]
Revenue	5,592,658	5,402,728
Fund related expense
Revenue from External Customer [Line Items]
Expenses	3,827,249	3,349,541
Revenue, net of related expenses
Revenue from External Customer [Line Items]
Revenue	1,765,409	2,053,187
Broker Commission
Revenue from External Customer [Line Items]
Revenue	63,542	65,212
Expenses	60,886	51,744
Financing activity, net
Revenue from External Customer [Line Items]
Revenue	2,656	13,468
Mutual fund administration revenue, net
Revenue from External Customer [Line Items]
Revenue	$ 1,768,065	$ 2,066,655

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-SubTopic 10
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