Investments in Affiliates - Summary of Transactions in, and Earnings from, Investments in Affiliates (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Investments In And Advances To Affiliates [Line Items]
Change in Unrealized Appreciation (Depreciation)	$ 0	$ (7,517)
Dividend Income	1,194,469	417,623
Affiliated Investments [Member] | Invesco Government & Agency Portfolio, Institutional Class [Member]
Investments In And Advances To Affiliates [Line Items]
Beginning Value	131,445,615	36,311,736
Purchases at Cost	26,186,027	28,845,709
Proceeds from Sales	(18,817,313)	(8,653,638)
Ending Value	138,814,329	56,503,807
Dividend Income	$ 1,194,469	$ 417,623