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Formation and Business Purpose (Details) - USD ($) $ in Thousands | 12 Months Ended | 163 Months Ended
--- | --- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2024
Summary of Investment Holdings [Line Items] |  |  |  |
Net proceeds from offerings of common stock | $ 67,690 | $ 21,241 | $ 40,006 | $ 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 | Minimum |  |  |  |
Summary of Investment Holdings [Line Items] |  |  |  |
Assets under management | $ 55,000,000 |  |  | $ 55,000,000

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