v3.23.3

Share Data and Net Assets - Schedule of Changes in Net Assets (Details) - USD ($) $ in Thousands |  |  | 12 Months Ended
--- | --- | --- | ---
Jan. 23, 2023 | Mar. 19, 2021 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2021
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |
Beginning of period (shares) |  |  | 61,125,000 |  |  |  |
Net assets at beginning of period |  |  | $ 1,245,563 | [1] | $ 1,312,823 |  | $ 914,879
Net investment income |  |  | 180,697 |  | 148,621 |  | 97,106
Net unrealized appreciation (depreciation) |  |  | (28,555) |  | (136,248) |  | 114,519
Net realized gains (losses) |  |  | (33,155) |  | 17,179 |  | 26,420
(Provision) benefit for taxes on realized and unrealized gains (losses) |  |  | (1,656) |  | (329) |  | (785)
Net increase (decrease) in net assets from stockholder transactions |  |  | (185,900) |  | (118,657) |  | (82,020)
Reclassification of additional paid-in capital |  |  |  |  |  |  | 0
Issuance of common stock in connection with the OSI2 Merger (shares) | 15,860,200 | 13,133,337 |  |  |  |  |
Issuance of common stock in connection with mergers |  |  | 334,034 |  | 0 |  | 242,704
Issuance of common stock in connection with the "at the market" offering |  |  | $ 1,300 |  | $ 20,622 |  | $ 0
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
Repurchase of common stock under dividend reinvestment plan |  |  | $ (2,418) |  | $ (1,857) |  | (2,170)
End of period (shares) |  |  | 77,225,000 |  | 61,125,000 |  |
Net assets at end of period |  |  | $ 1,515,764 | [1] | $ 1,245,563 | [1] | $ 1,312,823
Common Stock |  |  |  |  |  |  |
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |
Beginning of period (shares) |  |  | 61,125,000 |  | 60,120,000 |  | 46,987,000
Net assets at beginning of period |  |  | $ 611 |  | $ 601 |  | $ 470
Issuance of common stock in connection with the OSI2 Merger (shares) |  |  | 15,860,000 |  |  |  | 13,133,000
Issuance of common stock in connection with mergers |  |  | $ 159 |  |  |  | $ 131
Issuance of common stock in connection with the "at the market" offering (shares) |  |  | 69,000 |  | 934,000 |  |
Issuance of common stock in connection with the "at the market" offering |  |  | $ 1 |  | $ 9 |  |
Issuance of common stock under dividend reinvestment plan (shares) |  |  | 297,000 |  | 166,000 |  | 113,000
Issuance of common stock under dividend reinvestment plan |  |  | $ 3 |  | $ 2 |  | $ 1
Repurchase of common stock under dividend reinvestment plan (shares) |  |  | (126,000) |  | (95,000) |  | (113,000)
Repurchase of common stock under dividend reinvestment plan |  |  | $ (2) |  | $ (1) |  | $ (1)
End of period (shares) |  |  | 77,225,000 |  | 61,125,000 |  | 60,120,000
Net assets at end of period |  |  | $ 772 |  | $ 611 |  | $ 601
Additional paid-in-capital |  |  |  |  |  |  |
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |
Net assets at beginning of period |  |  | 1,827,721 |  | 1,805,557 |  | 1,488,713
Reclassification of additional paid-in capital |  |  |  |  |  |  | 74,271
Issuance of common stock in connection with mergers |  |  | 333,875 |  |  |  | 242,573
Issuance of common stock in connection with the "at the market" offering |  |  | 1,299 |  | 20,613 |  |
Issuance of common stock under dividend reinvestment plan |  |  | 5,851 |  | 3,407 |  | 2,169
Repurchase of common stock under dividend reinvestment plan |  |  | (2,416) |  | (1,856) |  | (2,169)
Net assets at end of period |  |  | 2,166,330 |  | 1,827,721 |  | 1,805,557
Accumulated Overdistributed Earnings |  |  |  |  |  |  |
Investment Company, Net Assets [Roll Forward] |  |  |  |  |  |  |
Net assets at beginning of period |  |  | (582,769) |  | (493,335) |  | (574,304)
Net investment income |  |  | 180,697 |  | 148,621 |  | 97,106
Net unrealized appreciation (depreciation) |  |  | (28,555) |  | (136,248) |  | 114,519
Net realized gains (losses) |  |  | (33,155) |  | 17,179 |  | 26,420
(Provision) benefit for taxes on realized and unrealized gains (losses) |  |  | (1,656) |  | (329) |  | (785)
Net increase (decrease) in net assets from stockholder transactions |  |  | (185,900) |  | (118,657) |  | (82,020)
Reclassification of additional paid-in capital |  |  |  |  |  |  | (74,271)
Net assets at end of period |  |  | $ (651,338) |  | $ (582,769) |  | $ (493,335)
[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 issued and outstanding shares and net asset value per share reflect the reverse stock split on a retroactive basis.

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