v3.25.2

Share Data and Net Assets - Schedule of Changes in Net Assets (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Jun. 30, 2025 | Mar. 31, 2025 | Dec. 31, 2024 | Jun. 30, 2024 | Mar. 31, 2024 | Dec. 31, 2023 | Jun. 30, 2025 | Jun. 30, 2024
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |  |
Beginning of period (in shares) |  |  | 82,245,000 |  |  |  | 82,245,000 |
Net assets at beginning of period | $ 1,475,113 | $ 1,449,815 | $ 1,487,811 | $ 1,524,099 | $ 1,511,651 | $ 1,515,764 | $ 1,487,811 | $ 1,515,764
Net investment income | 33,481 | 39,055 | 44,302 | 44,575 | 41,367 | 44,189 | 116,838 | 130,131
Net unrealized appreciation (depreciation) | 18,572 | (82,023) | (19,614) | 26,199 | (25,252) | (25,025) | (83,100) | (24,100)
Net realized gains (losses) | (13,432) | 6,705 | (17,310) | (69,452) | (6,603) | (8,453) | (24,000) | (84,500)
(Provision) benefit for taxes on realized and unrealized gains (losses) | (269) | 14 | (139) | (202) | (175) | (176) | (394) | (553)
Distributions to stockholders | (36,996) | (41,400) | (45,235) | (45,180) | (44,715) | (48,897) | $ (123,631) | $ (138,792)
Issuance of common stock under dividend reinvestment plan (in shares) |  |  |  |  |  |  | 639,964,000 | 295,484,000
Issuance of common stock under dividend reinvestment plan | 3,751 | 4,289 | 1,455 | 1,873 | 1,853 | 1,936 | $ 9,495 | $ 5,662
Repurchase of common stock under dividend reinvestment plan | (3,751) | (4,289) | (1,455) |  |  |  |  |
Issuance of common stock in connection with the "at the market" offering | 0 | 2,947 |  | 14,221 | 45,973 | 32,313 | 2,947 | 92,507
Issuance of common stock in private placement | $ 0 | 100,000 |  | 0 |  |  | $ 100,000 | 0
End of period (in shares) | 88,086,000 |  |  |  |  |  | 88,086,000 |
Net assets at end of period | $ 1,476,469 | $ 1,475,113 | $ 1,449,815 | $ 1,496,133 | $ 1,524,099 | $ 1,511,651 | $ 1,476,469 | $ 1,496,133
Common Stock |  |  |  |  |  |  |  |
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |  |
Beginning of period (in shares) | 88,086,000 | 82,245,000 | 82,245,000 | 81,396,000 | 78,965,000 | 77,225,000 | 82,245,000 | 77,225,000
Net assets at beginning of period | $ 881 | $ 822 | $ 822 | $ 814 | $ 790 | $ 772 | $ 822 | $ 772
Issuance of common stock under dividend reinvestment plan (in shares) | 269,000 | 276,000 | 95,000 | 100,000 | 97,000 | 99,000 |  |
Issuance of common stock under dividend reinvestment plan | $ 3 | $ 3 | $ 1 | $ 1 | $ 1 | $ 1 |  |
Repurchase of common stock under dividend reinvestment plan (in shares) | (269,000) | (276,000) | (95,000) |  |  |  |  |
Repurchase of common stock under dividend reinvestment plan | $ (3) | $ (3) | $ (1) |  |  |  |  |
Issuance of common stock in connection with the "at the market" offering (in shares) |  | 169,000 |  | 749,000 | 2,334,000 | 1,641,000 |  |
Issuance of common stock in connection with the "at the market" offering |  | $ 2 |  | $ 7 | $ 23 | $ 17 |  |
Issuance of common stock in a private placement (in shares) |  | 5,672,000 |  |  |  |  |  |
Issuance of common stock in private placement |  | $ 57 |  |  |  |  |  |
End of period (in shares) | 88,086,000 | 88,086,000 | 82,245,000 | 82,245,000 | 81,396,000 | 78,965,000 | 88,086,000 | 82,245,000
Net assets at end of period | $ 881 | $ 881 | $ 822 | $ 822 | $ 814 | $ 790 | $ 881 | $ 822
Additional paid-in-capital |  |  |  |  |  |  |  |
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |  |
Net assets at beginning of period | 2,367,337 | 2,264,449 | 2,264,449 | 2,248,363 | 2,200,561 | 2,166,330 | 2,264,449 | 2,166,330
Issuance of common stock under dividend reinvestment plan | 3,748 | 4,286 | 1,454 | 1,872 | 1,852 | 1,935 |  |
Repurchase of common stock under dividend reinvestment plan | (3,748) | (4,286) | (1,454) |  |  |  |  |
Issuance of common stock in connection with the "at the market" offering |  | 2,945 |  | 14,214 | 45,950 | 32,296 |  |
Issuance of common stock in private placement |  | 99,943 |  |  |  |  |  |
Net assets at end of period | 2,367,337 | 2,367,337 | 2,264,449 | 2,264,449 | 2,248,363 | 2,200,561 | 2,367,337 | 2,264,449
Accumulated Overdistributed Earnings |  |  |  |  |  |  |  |
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |  |
Net assets at beginning of period | (893,105) | (815,456) | (777,460) | (725,078) | (689,700) | (651,338) | (777,460) | (651,338)
Net investment income | 33,481 | 39,055 | 44,302 | 44,575 | 41,367 | 44,189 |  |
Net unrealized appreciation (depreciation) | 18,572 | (82,023) | (19,614) | 26,199 | (25,252) | (25,025) |  |
Net realized gains (losses) | (13,432) | 6,705 | (17,310) | (69,452) | (6,603) | (8,453) |  |
(Provision) benefit for taxes on realized and unrealized gains (losses) | (269) | 14 | (139) | (202) | (175) | (176) |  |
Distributions to stockholders | (36,996) | (41,400) | (45,235) | (45,180) | (44,715) | (48,897) |  |
Net assets at end of period | $ (891,749) | $ (893,105) | $ (815,456) | $ (769,138) | $ (725,078) | $ (689,700) | $ (891,749) | $ (769,138)

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