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FAIR VALUE HIERARCHY FOR INVESTMENTS—PORTFOLIO COMPOSITION - Percentage of Portfolio Investments by Type of Investment (Details) | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 100.00% | 100.00%
Investment Owned, At Cost | Investment Type Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 100.00% | 100.00%
Investment Owned, At Cost | Investment Type Concentration Risk | Other Portfolio investments |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 1.20% | 1.60%
Investment Owned, At Cost | Investment Type Concentration Risk | First lien debt |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 84.60% | 85.20%
Investment Owned, At Cost | Investment Type Concentration Risk | Equity |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 15.20% | 14.50%
Investment Owned, At Cost | Investment Type Concentration Risk | Equity Warrant |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 0.20% | 0.30%
Investment Owned, At Cost | Investment Type Concentration Risk | Other Portfolio investments |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 0.00% | 0.00%
Investment Owned, At Fair Value | Investment Type Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 100.00% | 100.00%
Investment Owned, At Fair Value | Investment Type Concentration Risk | Other Portfolio investments |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 1.30% | 2.00%
Investment Owned, At Fair Value | Investment Type Concentration Risk | First lien debt |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 76.20% | 77.60%
Investment Owned, At Fair Value | Investment Type Concentration Risk | Equity |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 23.20% | 22.00%
Investment Owned, At Fair Value | Investment Type Concentration Risk | Equity Warrant |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 0.60% | 0.40%
Investment Owned, At Fair Value | Investment Type Concentration Risk | Other Portfolio investments |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 0.00% | 0.00%

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