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Formation and Business Purpose (Details) - USD ($) $ in Thousands	6 Months Ended		169 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 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	$ 55,000,000		$ 55,000,000

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