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Significant Accounting Policies - Revenues From Contracts with Customers (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disaggregation of Revenue [Line Items]
Revenue	$ 39,014,433	$ 31,925,745
Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	36,569,103	30,157,680
Mutual fund administration revenue, net
Disaggregation of Revenue [Line Items]
Revenue	2,445,330	1,768,065
Proprietary funds
Disaggregation of Revenue [Line Items]
Revenue	28,956,031	25,222,628
Proprietary funds | Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	26,510,701	23,454,563
Proprietary funds | Mutual fund administration revenue, net
Disaggregation of Revenue [Line Items]
Revenue	2,445,330	1,768,065
Sub-advised funds and separately managed accounts
Disaggregation of Revenue [Line Items]
Revenue	10,058,402	6,703,117
Sub-advised funds and separately managed accounts | Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	10,058,402	6,703,117
Sub-advised funds and separately managed accounts | Mutual fund administration revenue, net
Disaggregation of Revenue [Line Items]
Revenue	$ 0	$ 0

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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