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Consolidated Schedule of Investments (Unaudited) - Investments (Details) (Parentheticals) | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
NAV % | 207.60% | 218.90%
Unrestricted Short Term Investments [Member] |  |
NAV % | 8.10% | 1.00%
Restricted Short Term Investments [Member] |  |
NAV % | 1.00% | 0.80%
Investment, Affiliated Issuer, Controlled [Member] |  |
NAV % | 9.50% | 4.40%
Investment, Affiliated Issuer, Controlled [Member] | Debt Securities [Member] |  |
NAV % | 20.30% |
Investment, Affiliated Issuer, Controlled [Member] | Debt Securities [Member] | Consumer-related Technologies [Member] |  |
NAV % |  | 1.60%
Investment, Affiliated Issuer, Controlled [Member] | Equity Securities [Member] |  |
NAV % | 5.30% |
Investment, Affiliated Issuer, Controlled [Member] | Equity Securities [Member] | Technology Sector [Member] |  |
NAV % |  | 0.90%
Investment, Affiliated Issuer, Controlled [Member] | Other Investments [Member] |  |
NAV % | 1.90% |
Investment, Affiliated Issuer, Controlled [Member] | Other Investments [Member] | Life Science [Member] |  |
NAV % |  | 1.90%
Investment, Affiliated Issuer, Noncontrolled [Member] |  |
NAV % |  | 0.30%
Investment, Affiliated Issuer, Noncontrolled [Member] | Debt Securities [Member] | Life Science [Member] |  |
NAV % |  | 0.30%
Investment, Affiliated Issuer, Noncontrolled [Member] | Equity Securities [Member] |  |
NAV % | 0.00% |
Investment, Affiliated Issuer, Noncontrolled [Member] | Equity Securities [Member] | Life Science [Member] |  |
NAV % |  | 0.00%
Investment, Affiliated Issuer, Noncontrolled [Member] | Warrant [Member] |  |
NAV % | 0.00% |
Investment, Affiliated Issuer, Noncontrolled [Member] | Warrant [Member] | Life Science [Member] |  |
NAV % |  | 0.00%
Investment, Affiliated Issuer, Noncontrolled [Member] | Other Investments [Member] |  |
NAV % | 2.50% |
Investment, Unaffiliated Issuer [Member] |  |
NAV % | 195.60% | 214.20%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] |  |
NAV % | 187.70% | 205.00%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Life Science [Member] |  |
NAV % |  | 75.60%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Technology Sector [Member] |  |
NAV % | 59.00% | 83.30%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Healthcare Information and Services Segment [Member] |  |
NAV % |  | 21.50%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Sustainability Segment [Member] |  |
NAV % | 19.90% | 24.60%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Life Science Segment [Member] |  |
NAV % | 77.80% |
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Software, Healthcare Information and Service [Member] |  |
NAV % | 31.00% |
Investment, Unaffiliated Issuer [Member] | Equity Securities [Member] |  |
NAV % | 2.50% | 1.50%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] |  |
NAV % | 5.40% | 7.60%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Technology Sector [Member] |  |
NAV % | 3.10% | 4.50%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Healthcare Information and Services Segment [Member] |  |
NAV % | 0.30% | 0.60%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Sustainability Segment [Member] |  |
NAV % | 0.10% | 0.20%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Life Science Segment [Member] |  |
NAV % | 1.90% | 2.30%
Investment, Unaffiliated Issuer [Member] | Other Investments [Member] | Life Science [Member] |  |
NAV % |  | 0.10%
Investment, Unaffiliated Issuer [Member] | Other Investments [Member] | Life Science Segment [Member] |  |
NAV % | 0.00% |

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