v3.23.3

Share Data and Net Assets - Narrative (Details) - USD ($) $ in Millions					12 Months Ended
	Feb. 08, 2023	Jan. 23, 2023	Feb. 07, 2022	Mar. 19, 2021	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Investment Company, Changes in Net Assets [Line Items]
Issuance of common stock in connection with the OSI2 Merger (shares)		15,860,200		13,133,337
Issuance of common stock under dividend reinvestment plan (shares)					297,336	165,651	112,573
Aggregate offering price	$ 125.0		$ 125.0
At the Market
Investment Company, Changes in Net Assets [Line Items]
Number of shares issued (in shares)					68,752	933,733
Net proceeds					$ 1.3	$ 20.6
Common Stock
Investment Company, Changes in Net Assets [Line Items]
Issuance of common stock under dividend reinvestment plan (shares)					171,645	70,794

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