v3.26.1
Note 9 - Concentrations of Credit Risk (Details Textual) - Debt Investments [Member]
3 Months Ended 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Dec. 31, 2025
Investment Concentration Risk [Member] | Reported Value Measurement [Member]      
Concentration Risk, Percentage 24.00%   26.00%
Investment Concentration Risk [Member] | Estimate of Fair Value Measurement [Member]      
Concentration Risk, Percentage 24.00%   26.00%
Interest and Fee Income [Member] | Reported Value Measurement [Member]      
Concentration Risk, Percentage 23.00% 24.00%  
Interest and Fee Income [Member] | Estimate of Fair Value Measurement [Member]      
Concentration Risk, Percentage 23.00% 24.00%