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v3.23.3

Consolidated Schedule of Investments (Unaudited) - Investments (Details) (Parentheticals) | Sep. 30, 2023 | Dec. 31, 2022
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NAV % | 210.40% | 226.10%
Investment, Affiliated Issuer, Controlled [Member] | Debt Securities [Member] |  |
NAV % | 3.80% |
Investment, Affiliated Issuer, Controlled [Member] | Debt Securities [Member] | Consumer-related Technologies [Member] |  |
NAV % | 1.30% |
Investment, Affiliated Issuer, Controlled [Member] | Preferred and Common Stock [Member] | Technology Sector [Member] |  |
NAV % | 0.70% |
Investment, Affiliated Issuer, Controlled [Member] | Other Investments [Member] | Biotechnology Sector [Member] |  |
NAV % | 1.80% |
Investment, Affiliated Issuer, Noncontrolled [Member] |  |
NAV % | 5.90% |
Investment, Affiliated Issuer, Noncontrolled [Member] | Debt Securities [Member] | Life Science [Member] |  |
NAV % | 3.50% |
Investment, Affiliated Issuer, Noncontrolled [Member] | Equity Securities [Member] | Life Science [Member] |  |
NAV % | 2.40% |
Investment, Affiliated Issuer, Noncontrolled [Member] | Warrant [Member] | Life Science [Member] |  |
NAV % | 0.00% |
Investment, Unaffiliated Issuer [Member] |  |
NAV % | 200.70% | 226.10%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] |  |
NAV % | 191.40% | 215.50%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Life Science [Member] |  |
NAV % | 69.70% | 99.70%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Technology Sector [Member] |  |
NAV % | 80.50% | 81.40%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Other Sustainability Sector [Member] |  |
NAV % | 23.80% |
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Sustainability Segment [Member] |  |
NAV % |  | 26.30%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Healthcare Sector [Member] |  |
NAV % | 17.40% | 8.10%
Investment, Unaffiliated Issuer [Member] | Equity Securities [Member] |  |
NAV % | 1.40% | 0.80%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] |  |
NAV % | 7.60% | 9.40%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Life Science [Member] |  |
NAV % |  | 3.10%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Technology Sector [Member] |  |
NAV % | 4.70% | 5.10%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Healthcare Information and Services Segment [Member] |  |
NAV % | 0.60% |
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Life Science Segment [Member] |  |
NAV % | 2.00% |
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Sustainability Segment [Member] |  |
NAV % | 0.20% | 0.60%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Healthcare Sector [Member] |  |
NAV % |  | 0.60%
Investment, Unaffiliated Issuer [Member] | Other Long-Term Investments [Member] |  |
NAV % |  | 0.40%
Investment, Unaffiliated Issuer [Member] | Other Long-Term Investments [Member] | Life Science [Member] |  |
NAV % | 0.30% |

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