v3.26.1
Investments in Affiliates - Summary of Transactions in, and Earnings from, Investments in Affiliates (Detail) - USD ($)
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Investments In And Advances To Affiliates [Line Items]        
Change in Unrealized Appreciation (Depreciation) $ 0 $ (37) $ 0 $ (7,554)
Dividend Income 1,105,600 1,283,878 2,300,069 1,701,501
Affiliated Investments [Member] | Invesco Government & Agency Portfolio, Institutional Class [Member]        
Investments In And Advances To Affiliates [Line Items]        
Beginning Value 138,814,329 56,503,807 131,445,615 36,311,736
Purchases at Cost 18,370,717 82,049,236 44,556,744 110,894,945
Proceeds from Sales (47,318,504) (992,083) (66,135,817) (9,645,721)
Ending Value 109,866,542 137,560,960 109,866,542 137,560,960
Dividend Income $ 1,105,600 $ 1,283,878 $ 2,300,069 $ 1,701,501