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FAIR VALUE OF FINANCIAL INSTRUMENTS (Fair Value of Derivative Instruments) (Details) - USD ($) | Jun. 30, 2018 | Dec. 31, 2017
--- | --- | ---
Derivatives, Fair Value [Line Items] |  |
Derivatives not Accounted for as Hedging Instruments | $ 14,279 | $ (568,922)
Commodity Contracts [Member] | Futures [Member] | Assets [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivatives not Accounted for as Hedging Instruments | $ 14,279 | $ (568,922)

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- Definition Unrealized gain (loss) on open commodity futures contracts. + References No definition available. + Details
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