Euro Deposits - Additional Information (Detail)	6 Months Ended	12 Months Ended
Jun. 30, 2026 USD ($)	Jun. 30, 2026 EUR (€)	Jun. 30, 2025 USD ($)	Dec. 31, 2025 EUR (€)	Jun. 30, 2026 EUR (€)	Dec. 31, 2025 USD ($)	Dec. 31, 2025 EUR (€)
Cash and Cash Equivalents [Abstract]
Annual nominal rate	1.30%				1.30%
Principal deposits	$ 618,308,024	€ 530,512,629	$ 445,997,531	€ 456,702,188
Principal redemptions	660,394,831	€ 562,804,727	$ 70,224,088	€ 258,336,581
Deposits, interest bearing	$ 374,469,947				€ 327,532,069	$ 422,598,808	€ 359,824,167

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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+ Details

- Definition

Rate of interest on investment.

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