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FAIR VALUE HIERARCHY FOR INVESTMENTS—PORTFOLIO COMPOSITION - Schedule of Level 3 Portfolio Investments (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 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 | (81,479) | (54,323)
New Investments | 146,064 | 78,544
Other | 0 | 0
Ending balance | 1,260,853 | 1,115,982
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 | 21,231 | 1,557
Investments | Net Unrealized Appreciation (Depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Gain (loss) included in earnings | (2,470) | (2,691)
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 | (74,862) | (50,999)
New Investments | 144,667 | 75,519
Other | (11,612) | (166)
Ending balance | 969,434 | 859,728
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 | 23,520 | 884
Debt | Net Unrealized Appreciation (Depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Gain (loss) included in earnings | (7,955) | (3,635)
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 | (6,617) | (3,324)
New Investments | 1,397 | 3,025
Other | 11,612 | 166
Ending balance | 285,951 | 255,622
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 | (2,289) | 673
Equity | Net Unrealized Appreciation (Depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Gain (loss) included in earnings | 4,295 | 1,053
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 | 0
Other | 0 | 0
Ending balance | 5,468 | 632
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 | 0
Equity Warrant | Net Unrealized Appreciation (Depreciation) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Gain (loss) included in earnings | $ 1,190 | $ (109)

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