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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