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Significant Accounting Policies - Mutual Fund Administration Revenue (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue from External Customer [Line Items]
Total revenue	$ 126,387,718	$ 136,624,380	$ 145,627,748
Administration revenue, gross
Revenue from External Customer [Line Items]
Total revenue	22,296,535	22,569,946	24,463,538
Fund related expense
Revenue from External Customer [Line Items]
Expenses	(15,048,850)	(13,989,139)	(14,183,370)
Revenue, net of related expenses
Revenue from External Customer [Line Items]
Total revenue	7,247,685	8,580,807	10,280,168
Broker Commission
Revenue from External Customer [Line Items]
Total revenue	245,594	240,459	332,680
Expenses	(230,791)	(206,295)	(302,905)
Financing activity, net
Revenue from External Customer [Line Items]
Total revenue	14,803	34,164	29,775
Mutual fund administration revenue, net
Revenue from External Customer [Line Items]
Total revenue	$ 7,262,488	$ 8,614,971	$ 10,309,943

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