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FINANCIAL INSTRUMENTS, OFF-BALANCE SHEET RISKS AND CONTINGENCIES (Additional Information) (Details) - USD ($)
Mar. 31, 2018
Dec. 31, 2017
Carrying Amounts and Fair Values of Financial Instruments or Liabilities [Line Items]    
Cash investments in money market funds $ 14,000,000 $ 19,000,000
Deposits in domestic and foreign financial institutions $ 64,851,142 $ 69,230,084