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Consolidated Schedule of Investments (Unaudited) - Investments (Details) (Parentheticals)	Jun. 30, 2023	Dec. 31, 2022
NAV %	201.40%	226.10%
Investment, Unaffiliated Issuer [Member]
NAV %	201.10%	226.10%
Investment, Unaffiliated Issuer [Member] | Warrant [Member]
NAV %	7.20%	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 %		3.10%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Life Science Segment [Member]
NAV %	1.80%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Sustainability Segment [Member]
NAV %	0.20%	0.60%
Investment, Unaffiliated Issuer [Member] | Warrant [Member] | Technology Sector [Member]
NAV %	4.60%	5.10%
Investment, Unaffiliated Issuer [Member] | Other Long-Term Investments [Member]
NAV %	0.40%	0.40%
Investment, Unaffiliated Issuer [Member] | Equity Securities [Member]
NAV %	1.20%	0.80%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member]
NAV %	192.30%	215.50%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Healthcare Sector [Member]
NAV %	10.10%	8.10%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Life Science [Member]
NAV %	82.90%	99.70%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Sustainability Segment [Member]
NAV %	23.40%	26.30%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member] | Technology Sector [Member]
NAV %	75.90%	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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