v3.23.3

Realized Gains or Losses and Net Unrealized Appreciation or Depreciation - Aggregate Net Realized Gains (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2021
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | $ (33,155) | $ 17,179 | $ 26,420
SIO2 Medical Products Inc. |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | (13,900) |  |
Convergeone Holdings Inc. |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | (6,000) |  |
Foreign currency forward contracts |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | (5,800) | 13,700 |
Aden & Anais Merger Sub Inc. |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | (5,200) |  |
Radiology Partners Inc. |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | (4,200) |  |
Carvana Co. |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | (2,800) |  |
Impel Neuropharma Inc. |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | (2,300) |  |
ASP Unifrax Holdings Inc. |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | (2,100) |  |
WP CPP Holdings LLC |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | (1,300) | (1,700) |
Global Medical Response Inc. |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | (1,000) |  |
Athenex Inc. |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | 6,500 |  |
Tersera Therapeutics LLC |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | 5,200 |  |
CorEvitas Group Holdings LP |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | 4,000 |  |
OmniSYS Acquisition Corporation |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) |  | 2,200 |
First Star Speir Aviation Limited |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) |  | 1,900 |
TigerConnect Inc. |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) |  | 1,800 |
PLATO Learning Inc. |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) |  |  | 7,800
Keypath Education Holdings, LLC |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) |  |  | 6,800
L Squared Capital Partners LLC |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) |  |  | 3,400
LTI Holdings, Inc. |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) |  |  | 2,600
BX Commercial Mortgage Trust 2020-VIVA |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) |  |  | 2,600
California Pizza Kitchen Inc. |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) |  |  | (1,800)
Refac Optical Group |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) |  |  | (1,300)
Other, net |  |  |
Schedule of Investments [Line Items] |  |  |
Net realized gains (losses) | $ (4,300) | $ (700) | $ 6,300

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