Derivative Instruments - Summary of Average Monthly Notional Value of Future Contracts Outstanding (Detail) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Weighted Average [Member] \| Currency Futures Contracts [Member]
Derivative [Line Items]
Average Notional Value - Long	$ 388,274,250	$ 822,173,133	$ 380,764,290	$ 581,681,705

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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