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FAIR VALUE OF FINANCIAL INSTRUMENTS (Fair Value of Derivative Instruments) (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Commodity Contracts [Member] | Futures - Commodity Contracts [Member] | Assets [Member]
Fair Value of Financial Instruments [Line Items]
Derivatives not Accounted for as Hedging Instruments	$ (67,021,257)	$ 55,721,680

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- Definition

Fair Value of Financial Instruments [Line Items]

+ References

No definition available.

+ Details

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- Definition

Fair value as of the balance sheet date of derivative instrument not designated as hedging instrument and classified as an asset.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

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