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Borrowings - NMNLC Credit Facility II (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Nov. 01, 2022 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Line of Credit Facility [Line Items] |  |  |  |
Amortization of financing costs |  |  | $ 6,866 | $ 7,502
Revolving Credit Facility | NMNLC Credit Facility II | Line of Credit |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Debt instrument, variable interest rate, type [Extensible Enumeration] |  |  | Secured Overnight Financing Rate (SOFR) [Member] |
Interest expense |  | $ 41 |  | 135
Non-usage fee |  | 0 |  | 1
Amortization of financing costs |  | $ 21 |  | $ 64
Weighted average interest rate |  | 7.60% |  | 7.60%
Effective interest rate |  | 11.70% |  | 11.40%
Average debt outstanding |  | $ 2,151 | $ 0 | $ 2,341
Revolving Credit Facility | NMNLC Credit Facility II | Line of Credit | 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 | Line of Credit | NMNLC |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Commitment fee percentage on unused capacity | 0.05% |  |  |
Revolving Credit Facility | NMNLC Credit Facility II | Line of Credit | NMNLC | Minimum |  |  |  |
Line of Credit Facility [Line Items] |  |  |  |
Interest rate margin | 0.35% |  |  |

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