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Significant Accounting Policies - Revenues From Contracts with Customers (Details) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation of Revenue [Line Items]
Revenue earned	$ 37,782,002	$ 35,134,129
Investment advisory
Disaggregation of Revenue [Line Items]
Revenue earned	34,631,290	31,833,471
Mutual Fund Administrative Services [Member]
Disaggregation of Revenue [Line Items]
Revenue earned	3,150,712	3,300,658
Proprietary funds
Disaggregation of Revenue [Line Items]
Revenue earned	30,455,911	28,219,224
Proprietary funds | Investment advisory
Disaggregation of Revenue [Line Items]
Revenue earned	27,305,199	24,918,566
Proprietary funds | Mutual Fund Administrative Services [Member]
Disaggregation of Revenue [Line Items]
Revenue earned	3,150,712	3,300,658
Sub-advised funds and institutional accounts
Disaggregation of Revenue [Line Items]
Revenue earned	7,326,091	6,914,905
Sub-advised funds and institutional accounts | Investment advisory
Disaggregation of Revenue [Line Items]
Revenue earned	7,326,091	6,914,905
Sub-advised funds and institutional accounts | Mutual Fund Administrative Services [Member]
Disaggregation of Revenue [Line Items]
Revenue earned	$ 0	$ 0

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 32
-Paragraph 2A
-URI http://asc.fasb.org/extlink&oid=82859839&loc=SL82860478-203043

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130543-203045

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130539-203045

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130545-203045

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