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Borrowings - NMNLC Credit Facility II (Details) - USD ($) $ in Thousands		3 Months Ended	6 Months Ended
	Nov. 01, 2022	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Line of Credit Facility [Line Items]
Amortization of financing costs			$ 4,539	$ 4,001
Revolving Credit Facility | NMNLC Credit Facility II | Credit Facility
Line of Credit Facility [Line Items]
Debt instrument, variable interest rate, type [Extensible Enumeration]			Secured Overnight Financing Rate (SOFR) [Member]
Interest expense		$ 49		94
Non-usage fee		1		1
Amortization of financing costs		$ 22		$ 43
Weighted average interest rate		7.60%		7.60%
Effective interest rate		11.20%		11.30%
Average debt outstanding		$ 2,505	$ 0	$ 2,438
Revolving Credit Facility | NMNLC Credit Facility II | Credit Facility | NMNLC And NM CLFX LP
Line of Credit Facility [Line Items]
Interest rate margin	2.25%
Maximum amount of borrowings available	$ 27,500
Revolving Credit Facility | NMNLC Credit Facility II | Credit Facility | NMNLC
Line of Credit Facility [Line Items]
Commitment fee percentage on unused capacity	0.05%
Revolving Credit Facility | NMNLC Credit Facility II | Credit Facility | Minimum | NMNLC
Line of Credit Facility [Line Items]
Interest rate margin	0.35%

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Amount of amortization expense attributable to debt issuance costs.

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