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v3.23.1

Consolidated Schedule of Investments (Unaudited) - Investments (Details) (Parentheticals) | Mar. 31, 2023 | Dec. 31, 2022
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NAV % | 222.40% | 226.10%
Investment, Unaffiliated Issuer [Member] |  |
NAV % | 221.10% | 226.10%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] |  |
NAV % | 8.00% | 9.40%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Healthcare Sector [Member] |  |
NAV % | 0.60% | 0.60%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Life Science [Member] |  |
NAV % | 2.10% | 3.10%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Sustainability Segment [Member] |  |
NAV % | 0.20% | 0.60%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Technology Sector [Member] |  |
NAV % | 5.10% | 5.10%
Investment, Unaffiliated Issuer [Member] | Other Long-Term Investments [Member] |  |
NAV % | 0.40% | 0.40%
Investment, Unaffiliated Issuer [Member] | Equity Securities [Member] |  |
NAV % | 0.90% | 0.80%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] |  |
NAV % | 212.80% | 215.50%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Healthcare Sector [Member] |  |
NAV % | 8.10% | 8.10%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Life Science [Member] |  |
NAV % | 95.70% | 99.70%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Sustainability Segment [Member] |  |
NAV % | 25.80% | 26.30%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Technology Sector [Member] |  |
NAV % | 83.20% | 81.40%
Investment, Affiliated Issuer, Noncontrolled [Member] |  |
NAV % | 0.30% |
Investment, Affiliated Issuer, Noncontrolled [Member] | Equity Securities [Member] | Life Science [Member] |  |
NAV % | 0.30% |

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