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FAIR VALUE OF FINANCIAL INSTRUMENTS (Valuation of Securities Using Fair Value Hierarchy) (Details) (USD $)
Mar. 31, 2013
Dec. 31, 2012
Short-Term Investments [Member]
   
Schedule of Trading Securities and Other Trading Assets [Line Items]    
Securities, fair value $ 22,902,282 $ 23,922,430
Exchange-Traded Futures Contracts [Member] | United States [Member]
   
Schedule of Trading Securities and Other Trading Assets [Line Items]    
Securities, fair value 4,023,690 (906,580)
Fair Value, Inputs, Level 1 [Member] | Short-Term Investments [Member]
   
Schedule of Trading Securities and Other Trading Assets [Line Items]    
Securities, fair value 22,902,282 23,922,430
Fair Value, Inputs, Level 1 [Member] | Exchange-Traded Futures Contracts [Member] | United States [Member]
   
Schedule of Trading Securities and Other Trading Assets [Line Items]    
Securities, fair value 4,023,690 (906,580)
Fair Value, Inputs, Level 2 [Member] | Short-Term Investments [Member]
   
Schedule of Trading Securities and Other Trading Assets [Line Items]    
Securities, fair value 0 0
Fair Value, Inputs, Level 2 [Member] | Exchange-Traded Futures Contracts [Member] | United States [Member]
   
Schedule of Trading Securities and Other Trading Assets [Line Items]    
Securities, fair value 0 0
Fair Value, Inputs, Level 3 [Member] | Short-Term Investments [Member]
   
Schedule of Trading Securities and Other Trading Assets [Line Items]    
Securities, fair value 0 0
Fair Value, Inputs, Level 3 [Member] | Exchange-Traded Futures Contracts [Member] | United States [Member]
   
Schedule of Trading Securities and Other Trading Assets [Line Items]    
Securities, fair value $ 0 $ 0