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FAIR VALUE OF FINANCIAL INSTRUMENTS (Effect of Derivative Instruments on Condensed Statements of Operations) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Realized Gain (Loss) on Derivatives Recognized in Income	$ (11,739)	$ 229,715	$ (2,271,270)
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income	522,819	(3,364,926)	5,217,980
Commodity Contracts [Member] | Futures [Member] | Realized gain (loss) on closed futures contracts
Derivative Instruments, Gain (Loss) [Line Items]
Realized Gain (Loss) on Derivatives Recognized in Income	(11,739)	229,715	(2,271,270)
Commodity Contracts [Member] | Futures [Member] | Change in unrealized gain (loss) on open positions
Derivative Instruments, Gain (Loss) [Line Items]
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income	$ 522,819	$ (3,364,926)	$ 5,217,980

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The net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open derivatives, commodity, or energy contracts, held at each balance sheet date, that was included in earnings for the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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