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Consolidated Schedule of Investments (Unaudited) - Investments (Details) (Parentheticals) | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
NAV % | 191.20% | 207.60%
Unrestricted Short Term Investments [Member] |  |
NAV % | 13.90% | 8.10%
Restricted Short Term Investments [Member] |  |
NAV % | 0.80% | 1.00%
Investment, Affiliated Issuer, Controlled [Member] |  |
NAV % | 0.40% | 9.50%
Investment, Affiliated Issuer, Controlled [Member] | Debt Securities [Member] |  |
NAV % | 0.40% | 2.30%
Investment, Affiliated Issuer, Controlled [Member] | Equity Securities [Member] |  |
NAV % | 0.00% | 5.30%
Investment, Affiliated Issuer, Controlled [Member] | Other Investments [Member] |  |
NAV % |  | 1.90%
Investment, Affiliated Issuer, Noncontrolled [Member] |  |
NAV % | 14.20% |
Investment, Affiliated Issuer, Noncontrolled [Member] | Debt Securities [Member] |  |
NAV % | 8.00% |
Investment, Affiliated Issuer, Noncontrolled [Member] | Equity Securities [Member] |  |
NAV % | 5.80% | 0.00%
Investment, Affiliated Issuer, Noncontrolled [Member] | Other Investments [Member] |  |
NAV % | 0.40% | 2.50%
Investment, Affiliated Issuer, Noncontrolled [Member] | Warrant [Member] |  |
NAV % | 0.00% | 0.00%
Investment, Unaffiliated Issuer [Member] |  |
NAV % | 176.60% | 195.60%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] |  |
NAV % | 169.10% | 187.70%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Life Science Segment [Member] |  |
NAV % | 84.40% | 77.80%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Sustainability Segment [Member] |  |
NAV % | 1.50% | 19.90%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Technology Sector [Member] |  |
NAV % | 50.70% | 59.00%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Healthcare Information and Services Segment [Member] |  |
NAV % | 32.50% | 31.00%
Investment, Unaffiliated Issuer [Member] | Equity Securities [Member] |  |
NAV % | 1.70% | 2.50%
Investment, Unaffiliated Issuer [Member] | Other Investments [Member] |  |
NAV % | 0.60% |
Investment, Unaffiliated Issuer [Member] | Other Investments [Member] | Life Science Segment [Member] |  |
NAV % |  | 0.00%
Investment, Unaffiliated Issuer [Member] | Other Investments [Member] | Technology Sector [Member] |  |
NAV % | 0.00% |
Investment, Unaffiliated Issuer [Member] | Other Investments [Member] | Healthcare Information and Services Segment [Member] |  |
NAV % | 0.60% |
Investment, Unaffiliated Issuer [Member] | Warrant [Member] |  |
NAV % | 5.20% | 5.40%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Life Science Segment [Member] |  |
NAV % | 2.00% | 1.90%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Sustainability Segment [Member] |  |
NAV % | 0.00% | 0.10%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Technology Sector [Member] |  |
NAV % | 3.10% | 3.10%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Healthcare Information and Services Segment [Member] |  |
NAV % | 0.10% | 0.30%

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