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Significant Accounting Policies - Revenue From Contracts with Customers (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Revenue	$ 136,624,380	$ 145,627,748	$ 145,201,729
Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	128,009,409	135,317,805	132,688,462
Mutual fund administration revenue, net
Disaggregation of Revenue [Line Items]
Revenue	8,614,971	10,309,943	12,513,267
Proprietary funds
Disaggregation of Revenue [Line Items]
Revenue	105,942,281	115,538,920	116,746,848
Proprietary funds | Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	97,327,310	105,228,977	104,233,581
Proprietary funds | Mutual fund administration revenue, net
Disaggregation of Revenue [Line Items]
Revenue	8,614,971	10,309,943	12,513,267
Sub-advised funds and separately managed accounts
Disaggregation of Revenue [Line Items]
Revenue	30,682,099	30,088,828	28,454,881
Sub-advised funds and separately managed accounts | Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	30,682,099	30,088,828	28,454,881
Sub-advised funds and separately managed accounts | Mutual fund administration revenue, net
Disaggregation of Revenue [Line Items]
Revenue	$ 0	$ 0	$ 0

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+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

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