Investments in Affiliates - Summary of Transactions in, and Earnings from, Investments in Affiliates (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Investments In And Advances To Affiliates [Line Items]
Change in Unrealized Appreciation (Depreciation)	$ (4,305)	$ 9,011	$ (7,833)	$ (30,807)
Dividend Income	476,170	180,263	1,488,559	231,405
Affiliated Investments [Member] | Money Market Mutual Fund - Invesco Government and Agency Portfolio - Institutional Class [Member]
Investments In And Advances To Affiliates [Line Items]
Beginning Value	32,326,552	31,740,361	68,087,284	31,507,548
Purchases at Cost	17,756,311	57,653,661	84,203,117	89,847,641
Proceeds from Sales	(21,607,885)	(56,913,080)	(123,815,423)	(88,874,247)
Ending Value	28,474,978	32,480,942	28,474,978	32,480,942
Dividend Income	$ 476,170	$ 180,263	$ 1,488,559	$ 231,405