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FAIR VALUE HIERARCHY FOR INVESTMENTS—PORTFOLIO COMPOSITION - Percentage of Portfolio Investments by Geographical Regions (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 | Geographic 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 | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 100.00% | 100.00%
Midwest | Investment Owned, At Cost | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 21.30% | 21.50%
Midwest | Investment Owned, At Fair Value | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 21.80% | 22.70%
West | Investment Owned, At Cost | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 20.80% | 18.70%
West | Investment Owned, At Fair Value | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 20.80% | 18.40%
Southwest | Investment Owned, At Cost | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 20.10% | 18.20%
Southwest | Investment Owned, At Fair Value | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 22.50% | 20.40%
Northeast | Investment Owned, At Cost | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 18.60% | 22.40%
Northeast | Investment Owned, At Fair Value | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 17.50% | 22.60%
Southeast | Investment Owned, At Cost | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 17.10% | 17.00%
Southeast | Investment Owned, At Fair Value | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 15.40% | 13.80%
Canada | Investment Owned, At Cost | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 1.10% | 1.20%
Canada | Investment Owned, At Fair Value | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 1.00% | 1.10%
Other Non-United States | Investment Owned, At Cost | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 1.00% | 1.00%
Other Non-United States | Investment Owned, At Fair Value | Geographic Concentration Risk |  |
Fair Value Measurement Inputs and Valuation Techniques [Line Items] |  |
Concentration risk, percentage (as a percent) | 1.00% | 1.00%

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