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Formation and Business Purpose (Details) - USD ($) $ in Thousands | 9 Months Ended | 172 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025
Summary of Investment Holdings [Line Items] |  |  |
Net proceeds from offerings of common stock | $ 0 | $ 67,691 | $ 1,034,550
Minimum |  |  |
Summary of Investment Holdings [Line Items] |  |  |
EBITDA as defined for middle market business | 10,000 |  |
Maximum |  |  |
Summary of Investment Holdings [Line Items] |  |  |
EBITDA as defined for middle market business | 200,000 |  |
New Mountain Capital |  |  |
Summary of Investment Holdings [Line Items] |  |  |
Assets under management | $ 60,000,000 |  | $ 60,000,000

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