Financial Highlights - Schedule of Net Asset Value Per Share (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net Asset Value
Net asset value per Share, beginning of period	$ 27.81	$ 25.62	$ 24.25
Net realized and change in unrealized gain (loss) on United States Treasury Obligations, Affiliated Investments and Currency Futures Contracts	(0.13)	2.12	1.55
Net investment income (loss)	1.16	0.32	(0.18)
Net income (loss)	1.03	2.44	1.37
Less: Return of capital distributions	(1.75)	(0.25)
Net asset value per Share, end of period	27.09	27.81	25.62
Market value per Share, beginning of period	27.81	25.63	24.26
Market value per Share, end of period	$ 27.09	$ 27.81	$ 25.63
Ratio to average Net Assets
Net investment income (loss)	4.11%	1.14%	(0.72%)
Expenses, after waivers	0.74%	0.73%	0.76%
Expenses, prior to waivers	0.79%	0.78%	0.78%
Total Return, at net asset value	(3.63%)	9.50%	5.65%
Total Return, at market value	(3.63%)	9.46%	5.65%