Derivative Instruments - Fair Value of Derivative Instruments (Detail) - Currency Futures Contracts [Member] - Not Designated as Hedging Instrument [Member] - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Derivatives, Fair Value [Line Items]
Assets	$ 8,564,400
Liabilities		$ (3,888,484)

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant