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Significant Accounting Policies - Summary of Investments Values Based Upon Level 1and Level 2 (Detail) - USD ($) | Jun. 30, 2015 | Dec. 31, 2014
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Level 1 Inputs |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Value of Investment | $ 80,175,798 | $ 62,595,546
Level 2 Inputs |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Value of Investment | $ 11,820,752 | $ 14,652,589

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