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Significant Accounting Policies - Revenues From Contracts with Customers (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Revenue	$ 28,248,929	$ 33,545,016	$ 60,174,674	$ 66,124,389
Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	26,698,993	31,510,672	56,856,673	62,023,389
Mutual fund administration revenue, net
Disaggregation of Revenue [Line Items]
Revenue	1,549,936	2,034,344	3,318,001	4,101,000
Proprietary funds
Disaggregation of Revenue [Line Items]
Revenue	21,272,678	26,369,713	46,495,306	52,016,246
Proprietary funds | Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	19,722,742	24,335,369	43,177,305	47,915,246
Proprietary funds | Mutual fund administration revenue, net
Disaggregation of Revenue [Line Items]
Revenue	1,549,936	2,034,344	3,318,001	4,101,000
Sub-advised funds and separately managed accounts
Disaggregation of Revenue [Line Items]
Revenue	6,976,251	7,175,303	13,679,368	14,108,143
Sub-advised funds and separately managed accounts | Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	6,976,251	7,175,303	13,679,368	14,108,143
Sub-advised funds and separately managed accounts | Mutual fund administration revenue, net
Disaggregation of Revenue [Line Items]
Revenue	$ 0	$ 0	$ 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.

+ 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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