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Significant Accounting Policies - Revenues From Contracts with Customers (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disaggregation of Revenue [Line Items]
Revenue	$ 33,545,016	$ 35,927,715	$ 66,124,389	$ 73,709,717
Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	31,510,672	33,526,273	62,023,389	68,157,563
Mutual fund administration, net
Disaggregation of Revenue [Line Items]
Revenue	2,034,344	2,401,442	4,101,000	5,552,154
Proprietary funds
Disaggregation of Revenue [Line Items]
Revenue	26,369,713	28,696,350	52,016,246	59,152,260
Proprietary funds | Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	24,335,369	26,294,908	47,915,246	53,600,106
Proprietary funds | Mutual fund administration, net
Disaggregation of Revenue [Line Items]
Revenue	2,034,344	2,401,442	4,101,000	5,552,154
Sub-advised funds and institutional accounts
Disaggregation of Revenue [Line Items]
Revenue	7,175,303	7,231,365	14,108,143	14,557,457
Sub-advised funds and institutional accounts | Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	7,175,303	7,231,365	14,108,143	14,557,457
Sub-advised funds and institutional accounts | Mutual fund administration, 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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