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Significant Accounting Policies - Summary of Investments Values Based Upon Level 1and Level 2 (Detail) - USD ($)	Sep. 30, 2015	Dec. 31, 2014
Level 1 Inputs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Value of Investment	$ 91,463,773	$ 62,595,546
Level 2 Inputs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Value of Investment	$ 11,379,148	$ 14,652,589

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- Definition

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