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Borrowings - NMNLC Credit Facility II (Details) - USD ($) $ in Thousands		3 Months Ended
	Nov. 01, 2022	Mar. 31, 2025	Mar. 31, 2024
Line of Credit Facility [Line Items]
Amortization of financing costs		$ 2,227	$ 1,985
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			45
Non-usage fee			0
Amortization of financing costs			$ 21
Weighted average interest rate			7.60%
Effective interest rate			11.40%
Average debt outstanding		$ 0	$ 2,371
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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