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Significant Accounting Policies - Revenues From Contracts with Customers (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Revenue	$ 31,925,745	$ 32,579,373
Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	30,157,680	30,512,718
Mutual fund administration revenue, net
Disaggregation of Revenue [Line Items]
Revenue	1,768,065	2,066,655
Proprietary funds
Disaggregation of Revenue [Line Items]
Revenue	25,222,628	25,646,532
Proprietary funds | Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	23,454,563	23,579,877
Proprietary funds | Mutual fund administration revenue, net
Disaggregation of Revenue [Line Items]
Revenue	1,768,065	2,066,655
Sub-advised funds and separately managed accounts
Disaggregation of Revenue [Line Items]
Revenue	6,703,117	6,932,841
Sub-advised funds and separately managed accounts | Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	6,703,117	6,932,841
Sub-advised funds and separately managed accounts | Mutual fund administration revenue, net
Disaggregation of Revenue [Line Items]
Revenue	$ 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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