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Service Providers and Related Party Agreements - Additional Information (Detail) - USD ($)
 3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Related Party Transaction [Line Items]    
Management fee percentage per annum of daily NAV 0.85%  
Managing owner waived fees $ 56,685 $ 28,406
Managing Owner [Member]    
Related Party Transaction [Line Items]    
Fee waiver termination notice period 60 days