v3.23.3

Share Data and Net Assets - Schedule of Distributions (Details) - USD ($) $ / shares in Units, $ in Thousands |  |  |  |  |  |  |  |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 29, 2023 | Jun. 30, 2023 | Mar. 31, 2023 | Dec. 30, 2022 | Sep. 30, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Dec. 31, 2021 | Sep. 30, 2021 | Jun. 30, 2021 | Mar. 31, 2021 | Dec. 31, 2020 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2019
Investment Company, Changes in Net Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount per share (in dollars per share) |  |  |  |  |  |  |  |  |  |  |  |  | $ 2.61 | $ 1.95 | $ 1.515 | $ 1.17 | $ 1.14
Distributions to stockholders |  |  |  |  |  |  |  |  |  |  |  |  | $ 180,000 | $ 115,300 | $ 79,800 |  |
Issuance of common stock under dividend reinvestment plan (shares) |  |  |  |  |  |  |  |  |  |  |  |  | 297,336 | 165,651 | 112,573 |  |
Issuance of common stock under dividend reinvestment plan |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,854 | $ 3,409 | $ 2,170 |  |
Quarterly |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investment Company, Changes in Net Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount per share (in dollars per share) | $ 0.55 | $ 0.55 | $ 0.55 | $ 0.54 | $ 0.51 | $ 0.495 | $ 0.48 | $ 0.465 | $ 0.435 | $ 0.39 | $ 0.36 | $ 0.33 |  |  |  |  |
Distributions to stockholders | $ 40,900 | $ 41,300 | $ 41,100 | $ 32,000 | $ 30,200 | $ 29,400 | $ 28,500 | $ 27,200 | $ 25,500 | $ 22,900 | $ 16,400 | $ 15,000 |  |  |  |  |
Issuance of common stock under dividend reinvestment plan (shares) | 76,766 | 57,279 | 68,412 | 53,369 | 51,181 | 43,676 | 34,804 | 35,990 | 28,358 | 25,660 | 27,234 | 31,321 |  |  |  |  |
Issuance of common stock under dividend reinvestment plan | $ 1,500 | $ 1,100 | $ 1,300 | $ 1,100 | $ 1,000 | $ 900 | $ 800 | $ 800 | $ 600 | $ 500 | $ 500 | $ 500 |  |  |  |  |
Special |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investment Company, Changes in Net Assets [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Amount per share (in dollars per share) |  |  |  | $ 0.42 |  |  |  |  |  |  |  |  |  |  |  |  |
Distributions to stockholders |  |  |  | $ 24,800 |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common stock under dividend reinvestment plan (shares) |  |  |  | 41,510 |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common stock under dividend reinvestment plan |  |  |  | $ 800 |  |  |  |  |  |  |  |  |  |  |  |  |

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