v3.23.3

Portfolio Investments - Summarized Statement of Operations Information (Details) - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2021
Investment Company, Nonconsolidated Subsidiary [Line Items] |  |  |  |
Total investment income |  | $ 379,286 | $ 262,520 | $ 209,385
Interest expense |  | 111,642 | 46,929 | 30,518
Total expenses |  | 204,036 | 113,591 | 111,092
Net investment income before taxes |  | 180,775 | 151,929 | 99,901
Net increase (decrease) in net assets resulting from operations |  | 117,331 | 29,223 | 237,260
SLF JV I |  |  |  |
Investment Company, Nonconsolidated Subsidiary [Line Items] |  |  |  |
Interest income |  | 38,984 | 24,014 | 20,018
Fee income |  | 290 | 198 | 565
Total investment income |  | 39,274 | 24,212 | 20,583
Other expenses |  | 442 | 253 | 260
Total expenses |  | 33,988 | 17,112 | 14,410
Net investment income before taxes |  | 5,286 | 7,100 | 6,173
Net unrealized appreciation (depreciation) |  | 13,416 | (23,661) | 13,270
Realized gain (loss) |  | (10,962) | 534 | 399
Net increase (decrease) in net assets resulting from operations |  | 7,740 | (16,027) | 19,842
SLF JV I | Senior Credit Facility |  |  |  |
Investment Company, Nonconsolidated Subsidiary [Line Items] |  |  |  |
Interest expense |  | 19,002 | 7,713 | 5,706
SLF JV I | SLF JV I Notes |  |  |  |
Investment Company, Nonconsolidated Subsidiary [Line Items] |  |  |  |
Interest expense |  | 14,544 | 9,146 | $ 8,444
OCSI Glick JV LLC |  |  |  |
Investment Company, Nonconsolidated Subsidiary [Line Items] |  |  |  |
Interest income | $ 4,643 | 14,043 | 9,703 |
Fee income | 67 | 63 | 149 |
Total investment income | 4,710 | 14,106 | 9,852 |
Other expenses | 95 | 182 | 168 |
Total expenses | 3,032 | 12,798 | 6,491 |
Net investment income before taxes | 1,678 | 1,308 | 3,361 |
Net unrealized appreciation (depreciation) | (1,710) | 1,254 | (3,216) |
Realized gain (loss) | 32 | (2,562) | (145) |
Net increase (decrease) in net assets resulting from operations | 0 | 0 | 0 |
OCSI Glick JV LLC | Senior Credit Facility |  |  |  |
Investment Company, Nonconsolidated Subsidiary [Line Items] |  |  |  |
Interest expense | 1,157 | 6,560 | 2,747 |
OCSI Glick JV LLC | Glick JV Notes |  |  |  |
Investment Company, Nonconsolidated Subsidiary [Line Items] |  |  |  |
Interest expense | $ 1,780 | $ 6,056 | $ 3,576 |

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