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FAIR VALUE OF FINANCIAL INSTRUMENTS - Effect of Derivative Instruments on Condensed Statements of Operations (Details) - USD ($)
9 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Derivative Instruments, Gain (Loss) [Line Items]    
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income $ 30,374,062 $ (35,120,220)
Commodity Contracts [Member] | Futures - Commodity Contracts [Member]    
Derivative Instruments, Gain (Loss) [Line Items]    
Realized Gain (Loss) on Derivatives Recognized in Income (57,790,242) 84,114,483
Change in Unrealized Gain (Loss) on Derivatives Recognized in Income $ 30,374,062 $ (35,120,220)