Service Providers and Related Party Agreements - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Related Party Transaction [Line Items]
Managing owner waived fees	$ 10,057	$ 103,294	$ 72,077	$ 449,092
The Managing Owner [Member]
Related Party Transaction [Line Items]
Management fee percentage per annum of daily NAV			0.75%
Fee waiver termination notice period			60 days’