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FAIR VALUE HIERARCHY FOR INVESTMENTS—PORTFOLIO COMPOSITION - Schedule of Level 3 Portfolio Investments (Details) - USD ($) $ in Thousands | 9 Months Ended
--- | ---
Sep. 30, 2025 | Sep. 30, 2024
Investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | $ 1,177,507 | $ 1,092,895
Transfers Into Level 3 Hierarchy | 0 | 0
Redemptions/ Repayments | (252,020) | (181,567)
New Investments | 298,643 | 275,827
Other | 0 | 0
Ending balance | 1,260,202 | 1,162,627
Investments | Net Changes from Unrealized to Realized |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Gain (loss) included in earnings | 24,361 | (25,304)
Investments | Net Unrealized Appreciation (Depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Gain (loss) included in earnings | 11,711 | 776
Debt |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | 895,676 | 838,125
Transfers Into Level 3 Hierarchy | 0 | 0
Redemptions/ Repayments | (239,393) | (169,492)
New Investments | 292,734 | 264,572
Other | (17,370) | (166)
Ending balance | 947,599 | 917,839
Debt | Net Changes from Unrealized to Realized |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Gain (loss) included in earnings | 31,628 | 2,180
Debt | Net Unrealized Appreciation (Depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Gain (loss) included in earnings | (15,676) | (17,380)
Equity |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | 277,553 | 254,029
Transfers Into Level 3 Hierarchy | 0 | 0
Redemptions/ Repayments | (12,627) | (12,075)
New Investments | 5,909 | 10,127
Other | 17,370 | 166
Ending balance | 305,305 | 242,840
Equity | Net Changes from Unrealized to Realized |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Gain (loss) included in earnings | (7,267) | (27,394)
Equity | Net Unrealized Appreciation (Depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Gain (loss) included in earnings | 24,367 | 17,987
Equity Warrant |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Beginning balance | 4,278 | 741
Transfers Into Level 3 Hierarchy | 0 | 0
Redemptions/ Repayments | 0 | 0
New Investments | 0 | 1,128
Other | 0 | 0
Ending balance | 7,298 | 1,948
Equity Warrant | Net Changes from Unrealized to Realized |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Gain (loss) included in earnings | 0 | (90)
Equity Warrant | Net Unrealized Appreciation (Depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Gain (loss) included in earnings | $ 3,020 | $ 169

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