Derivative Instruments - Effect of Derivative Instruments on Statements of Income and Expenses (Detail) - Currency Futures Contracts [Member] - Not Designated as Hedging Instrument [Member] - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Derivative Instruments, Gain (Loss) [Line Items]
Futures contracts, realized gain (loss)	$ 11,195,317	$ (11,617,887)	$ 7,653,997	$ (36,671,680)
Futures contracts, unrealized gain (loss)	(2,131,225)	(2,916,978)	12,452,884	2,989,942
Future Contracts, Net Realized and Unrealized Gain (Loss)	$ 9,064,092	$ (14,534,865)	$ 20,106,881	$ (33,681,738)