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Formation and Business Purpose (Details) - USD ($) $ in Thousands | 9 Months Ended | 148 Months Ended
--- | --- | ---
Sep. 30, 2023 | Sep. 30, 2022 | Sep. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract] |  |  |
Net proceeds from offerings of common stock | $ 6,625 | $ 40,006 | $ 952,242
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 | $ 45,000,000 |  | $ 45,000,000

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