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FAIR VALUE OF FINANCIAL INSTRUMENTS - Fair Value of Derivative Instruments (Details) - USD ($) | Jun. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Derivatives, Fair Value [Line Items] |  |
Derivatives not Accounted for as Hedging Instruments | $ (540,026) | $ (46,103)
Commodity Contracts [Member] | Futures [Member] | Assets [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivatives not Accounted for as Hedging Instruments | $ (540,026) | $ (46,103)

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