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Derivative Instruments - Summary of Average Monthly Notional Value of Future Contracts Outstanding (Detail) - USD ($)
3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Weighted Average [Member] | Currency Futures Contract [Member]    
Derivative [Line Items]    
Average Notional Value - Short $ (39,648,283) $ (32,998,348)