Derivative Instruments - Effect of Derivative Instruments on Statements of Income and Expenses (Detail) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Futures contracts, realized gain (loss)	$ 3,553,040	$ 726,024	$ 340,449
Futures contracts, unrealized gain (loss)	(6,736,124)	5,518,432	1,223,352
Commodity Futures Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Futures contracts, realized gain (loss)	3,553,040	726,024	340,449
Futures contracts, unrealized gain (loss)	(6,736,124)	5,518,432	1,223,352
Net realized and net change in unrealized gain (loss)	$ (3,183,084)	$ 6,244,456	$ 1,563,801

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Amount of realized and unrealized gain (loss) on investment.

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The difference between the book value and the sale price of agreements to purchase or sell mineral resources, energy, and agricultural products at some future point. This element refers to the gain (loss) included in earnings and not to the cash proceeds.

+ References

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of open agreements to purchase or sell mineral resources, energy, and agricultural products at some future point held at each balance sheet date, that was included in earnings for the period.

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