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Organization and Nature of Business Operations (Details) - Portfolio Concentration Risk
3 Months Ended 12 Months Ended
Mar. 31, 2016
Dec. 31, 2015
Market Based Securities | Available-for-sale Securities    
Concentration Risk [Line Items]    
Percentage of portfolio invested 97.30% 100.00%
Trading Securities | Trading Securities    
Concentration Risk [Line Items]    
Percentage of portfolio invested 2.70%