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FAIR VALUE OF FINANCIAL INSTRUMENTS - Effect of Derivative Instruments (Details) - USD ($)	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income	$ 13,130,099	$ 5,462,074
Commodity Contracts | Realized gain (loss) on closed positions
Derivative Instruments, Gain (Loss) [Line Items]
Realized Gain (Loss) on Derivatives Recognized in Income	(1,925,589)	10,264,256
Commodity Contracts | Change in unrealized gain (loss) on open positions
Derivative Instruments, Gain (Loss) [Line Items]
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income	$ 13,130,099	$ 5,462,074

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The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

+ 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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13(h))
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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.

+ References

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-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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