v3.23.3

Financial Highlights - Portfolio Composition (Details) $ / shares in Units, shares in Thousands, $ in Thousands |  |  |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | ---
Jun. 30, 2023 $ / shares | Mar. 31, 2023 $ / shares | Jan. 20, 2023 | Jun. 30, 2022 $ / shares | Mar. 31, 2022 $ / shares | Dec. 31, 2021 $ / shares | Sep. 30, 2023 USD ($) $ / shares shares | Sep. 30, 2022 USD ($) $ / shares shares | Sep. 30, 2021 USD ($) $ / shares shares | Sep. 30, 2020 USD ($) $ / shares shares | Sep. 30, 2019 USD ($) $ / shares shares
Investment Company, Financial Highlights [Roll Forward] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net asset value per share at beginning of period (in dollars per share) |  |  |  |  |  |  | $ 20.38 | [1] | $ 21.84 | [1] | $ 19.47 |  | $ 19.81 | $ 18.26
Net investment income (in dollars per share) |  |  |  |  |  |  | 2.51 | [2] | 2.45 | [2] | 1.80 | [2] | 1.53 | 1.45
Net unrealized appreciation (depreciation) (in dollars per share) |  |  |  |  |  |  | (0.17) |  | (2.23) |  | 2.19 |  | (0.44) | 0.82
Net realized gains (losses) (in dollars per share) |  |  |  |  |  |  | (0.46) |  | 0.28 |  | 0.49 |  | (0.30) | 0.44
(Provision) benefit for taxes on realized and unrealized gains (losses) (in dollars per share) |  |  |  |  |  |  | (0.02) |  | (0.01) |  | (0.02) |  | 0.04 | (0.02)
Distributions of net investment income to stockholders (dollars per share) |  |  |  |  |  |  | (2.61) |  | (1.95) |  | (1.515) |  | (1.17) | (1.14)
Issuance of common stock (in dollars per share) |  |  |  |  |  |  | 0 |  | 0 |  | (0.57) |  | 0 | 0
Net asset value per share at end of period (in dollars per share) | $ 19.58 | $ 19.66 |  | $ 20.67 | $ 21.79 | $ 22.03 | 19.63 | [1] | 20.38 | [1] | 21.84 | [1] | 19.47 | 19.81
Per share market value at beginning of period (in dollars per share) |  |  |  |  |  |  | 18.00 |  | 21.18 |  | 14.52 |  | 15.54 | 14.88
Per share market value at end of period (in dollars per share) |  |  |  |  |  |  | $ 20.12 |  | $ 18.00 |  | $ 21.18 |  | $ 14.52 | $ 15.54
Total return |  |  |  |  |  |  | 27.30% |  | (6.71%) |  | 57.61% |  | 2.10% | 12.56%
Common shares outstanding at beginning of period (in shares) | shares |  |  |  |  |  |  | 61,125 | [1] | 60,120 | [1] | 46,987 |  | 46,987 | 46,987
Common shares outstanding at end of period (in shares) | shares |  |  |  |  |  |  | 77,225 | [1] | 61,125 | [1] | 60,120 | [1] | 46,987 | 46,987
Net assets at beginning of period | $ |  |  |  |  |  |  | $ 1,245,563 |  | $ 1,312,823 |  | $ 914,879 |  | $ 930,630 | $ 858,035
Net assets at end of period | $ |  |  |  |  |  |  | 1,515,764 |  | 1,245,563 |  | 1,312,823 |  | 914,879 | 930,630
Average net assets | $ |  |  |  |  |  |  | $ 1,437,728 |  | $ 1,308,518 |  | $ 1,150,662 |  | $ 871,305 | $ 909,264
Ratio of net investment income to average net assets |  |  |  |  |  |  | 12.57% |  | 11.36% |  | 8.44% |  | 8.26% | 7.47%
Ratio of total expenses to average net assets |  |  |  |  |  |  | 14.19% |  | 8.68% |  | 9.65% |  | 7.57% | 9.65%
Ratio of net expenses to average net assets |  |  |  |  |  |  | 13.81% |  | 8.45% |  | 9.51% |  | 8.16% | 8.78%
Ratio of portfolio turnover to average investments at fair value |  |  |  |  |  |  | 26.12% |  | 26.99% |  | 39.66% |  | 38.99% | 32.50%
Weighted average outstanding debt | $ |  |  |  |  |  |  | $ 1,659,701 |  | $ 1,361,151 |  | $ 964,390 |  | $ 647,080 | $ 573,891
Average debt per share (dollars per share) |  |  |  |  |  |  | $ 23.01 |  | $ 22.41 |  | $ 17.85 |  | $ 13.77 | $ 12.21
Asset coverage ratio |  |  |  |  |  |  | 187.74% |  | 188.64% |  | 201.68% |  | 227.22% | 294.91%
Stock split, conversion ratio |  |  | 0.0033 |  |  |  | 0.3333 |  |  |  |  |  |  |
[1] | As discussed in Note 2, the Company completed a 1-for-3 reverse stock split on January 20, 2023, effective as of the commencement of trading on January 23, 2023. The weighted average common shares outstanding and per share information reflect the reverse stock split on a retroactive basis.
[2] | As discussed in Note 2, the Company completed a 1-for-3 reverse stock split on January 20, 2023, effective as of the commencement of trading on January 23, 2023. The weighted average common shares outstanding and per share information reflect the reverse stock split on a retroactive basis.

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