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Significant Accounting Policies - Revenues From Contracts with Customers (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Revenue	$ 32,579,373	$ 37,782,002
Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	30,512,718	34,631,290
Mutual fund administration, net
Disaggregation of Revenue [Line Items]
Revenue	2,066,655	3,150,712
Proprietary funds
Disaggregation of Revenue [Line Items]
Revenue	25,646,532	30,455,911
Proprietary funds | Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	23,579,877	27,305,199
Proprietary funds | Mutual fund administration, net
Disaggregation of Revenue [Line Items]
Revenue	2,066,655	3,150,712
Sub-advised funds and institutional accounts
Disaggregation of Revenue [Line Items]
Revenue	6,932,841	7,326,091
Sub-advised funds and institutional accounts | Investment advisory
Disaggregation of Revenue [Line Items]
Revenue	6,932,841	7,326,091
Sub-advised funds and institutional accounts | Mutual fund administration, net
Disaggregation of Revenue [Line Items]
Revenue	$ 0	$ 0

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130543-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130539-203045

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130545-203045

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