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Significant Accounting Policies - Summary of Investments Values Based Upon Fair Value Hierarchy(Detail) | Sep. 30, 2016 USD ($)
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Fair Value, Measurements, Recurring [Member] |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Cash equivalents | $ 56,074,210
Seed capital equity method investments | 27,952,788
Deferred compensation investments | 13,369,919
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Cash equivalents | 56,074,210
Seed capital equity method investments | 26,454,627
Deferred compensation investments | 13,369,919
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Cash equivalents | 0
Seed capital equity method investments | 0
Deferred compensation investments | 0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Cash equivalents | 0
Seed capital equity method investments | 0
Deferred compensation investments | 0
Seed capital investments |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Trading Investments | 20,224
Seed capital investments | Fair Value, Measurements, Recurring [Member] |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Trading Investments | 20,224
Seed capital investments | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Trading Investments | 20,224
Seed capital investments | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Trading Investments | 0
Seed capital investments | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Trading Investments | 0
Securities held in Consolidated Funds |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Trading Investments | 45,704,913
Securities held in Consolidated Funds | Fair Value, Measurements, Recurring [Member] |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Trading Investments | 45,704,913
Securities held in Consolidated Funds | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member] |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Trading Investments | 17,517,463
Securities held in Consolidated Funds | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Trading Investments | 28,187,450
Securities held in Consolidated Funds | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member] |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Trading Investments | 0
Equity Method Investments [Member] |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |
Investments measured at NAV | $ 1,498,161

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- Definition Fair value of investments in certain entities that calculate net asset value per share, including, but not limited to, by unit, membership interest, or other ownership interest. Investments include, but are not limited to, investments in certain hedge funds, venture capital funds, private equity funds, real estate partnerships or funds. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 6A -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=66048111&loc=SL6742756-110258 + Details
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- Definition Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 + Details
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- Definition Fair value portion of investments accounted under the equity method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 25 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=66022186&loc=d3e32014-111567 + Details
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- Definition Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26626-111562 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 + Details
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