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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Borrowings - NMFC Credit Facility (Details) € in Thousands, £ in Thousands, $ in Thousands			3 Months Ended		9 Months Ended
	Jul. 30, 2026 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2026 EUR (€)	Sep. 30, 2026 GBP (£)	Dec. 31, 2025 USD ($)	Dec. 31, 2025 EUR (€)	Dec. 31, 2025 GBP (£)	Sep. 30, 2025 EUR (€)	Sep. 30, 2025 GBP (£)
Line of Credit Facility [Line Items]
Amortization of financing costs					$ 7,128	$ 6,866
NMFC Credit Facility
Line of Credit Facility [Line Items]
Credit facility outstanding balance			$ 30,212		30,212				$ 81,074
Revolving Credit Facility \| NMFC Credit Facility
Line of Credit Facility [Line Items]
Credit facility outstanding balance			30,212		30,212		€ 16,512	£ 8,666	$ 81,074	€ 16,512	£ 8,666	€ 16,512	£ 8,666
Revolving Credit Facility \| NMFC Credit Facility \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 537,100
Commitment fee percentage on unused capacity	0.375%	0.375%
Interest expense			371	$ 390	2,248	1,149
Non-usage fee			482	476	1,340	1,563
Amortization of financing costs			$ 223	$ 189	$ 633	$ 560
Weighted average interest rate			4.80%	4.70%	5.10%	5.00%
Effective interest rate			13.90%	13.50%	9.70%	14.60%
Average debt outstanding			$ 30,658	$ 30,991	$ 58,155	$ 29,879
Extending Lenders \| Revolving Credit Facility \| NMFC Credit Facility \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 487,100	$ 527,100
Basis spread on variable rate	1.90%	1.90%
Non-Extending Lenders \| Revolving Credit Facility \| NMFC Credit Facility \| Line of Credit
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 50,000
Basis spread on variable rate	2.00%	2.10%