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Significant Accounting Policies - Revenues From Contracts with Customers (Details) - USD ($) | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue earned | $ 37,471,647 | $ 36,771,629 | $ 111,181,363 | $ 107,353,244
Investment advisory |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue earned | 34,928,205 | 33,782,603 | 103,085,767 | 98,105,905
Mutual fund administration, net |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue earned | 2,543,442 | 2,989,026 | 8,095,596 | 9,247,339
Proprietary funds |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue earned | 29,408,277 | 29,560,917 | 88,560,537 | 86,223,079
Proprietary funds | Investment advisory |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue earned | 26,864,835 | 26,571,891 | 80,464,941 | 76,975,740
Proprietary funds | Mutual fund administration, net |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue earned | 2,543,442 | 2,989,026 | 8,095,596 | 9,247,339
Sub-advised funds and institutional accounts |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue earned | 8,063,370 | 7,210,712 | 22,620,826 | 21,130,165
Sub-advised funds and institutional accounts | Investment advisory |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue earned | 8,063,370 | 7,210,712 | 22,620,826 | 21,130,165
Sub-advised funds and institutional accounts | Mutual fund administration, net |  |  |  |
Disaggregation of Revenue [Line Items] |  |  |  |
Revenue earned | $ 0 | $ 0 | $ 0 | $ 0

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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 + Details
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