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Consolidated Schedule of Investments (Unaudited) - Investments (Details) (Parentheticals)	Mar. 31, 2024	Dec. 31, 2023
NAV %	214.10%	218.90%
Investment, Affiliated Issuer, Controlled [Member]
NAV %	4.10%	4.40%
Investment, Affiliated Issuer, Controlled [Member] | Consumer-related Technologies [Member] | Debt Securities [Member]
NAV %	1.50%	1.60%
Investment, Affiliated Issuer, Controlled [Member] | Life Science [Member] | Other Investments [Member]
NAV %	1.80%	1.90%
Investment, Affiliated Issuer, Controlled [Member] | Technology Sector [Member] | Equity Securities [Member]
NAV %	0.80%	0.90%
Investment, Affiliated Issuer, Noncontrolled [Member]
NAV %		0.30%
Investment, Affiliated Issuer, Noncontrolled [Member] | Debt Securities [Member]
NAV %	3.80%
Investment, Affiliated Issuer, Noncontrolled [Member] | Life Science [Member] | Debt Securities [Member]
NAV %	3.80%	0.30%
Investment, Affiliated Issuer, Noncontrolled [Member] | Life Science [Member] | Equity Securities [Member]
NAV %	0.00%	0.00%
Investment, Affiliated Issuer, Noncontrolled [Member] | Life Science [Member] | Warrant [Member]
NAV %	0.00%	0.00%
Investment, Unaffiliated Issuer [Member]
NAV %	206.20%	214.20%
Investment, Unaffiliated Issuer [Member] | Debt Securities [Member]
NAV %	196.60%	205.00%
Investment, Unaffiliated Issuer [Member] | Equity Securities [Member]
NAV %	1.40%	1.50%
Investment, Unaffiliated Issuer [Member] | Warrant [Member]
NAV %	7.20%	7.60%
Investment, Unaffiliated Issuer [Member] | Life Science [Member] | Debt Securities [Member]
NAV %		75.60%
Investment, Unaffiliated Issuer [Member] | Life Science [Member] | Other Investments [Member]
NAV %	1.00%	0.10%
Investment, Unaffiliated Issuer [Member] | Life Science [Member] | Debt Investments [Member]
NAV %	76.80%
Investment, Unaffiliated Issuer [Member] | Technology Sector [Member] | Debt Securities [Member]
NAV %	77.60%	83.30%
Investment, Unaffiliated Issuer [Member] | Technology Sector [Member] | Warrant [Member]
NAV %	4.60%	4.50%
Investment, Unaffiliated Issuer [Member] | Healthcare Information and Services Segment [Member] | Debt Securities [Member]
NAV %	21.00%	21.50%
Investment, Unaffiliated Issuer [Member] | Healthcare Information and Services Segment [Member] | Warrant [Member]
NAV %	0.40%	0.60%
Investment, Unaffiliated Issuer [Member] | Life Science Segment [Member] | Warrant [Member]
NAV %	2.00%	2.30%
Investment, Unaffiliated Issuer [Member] | Sustainability Segment [Member] | Debt Securities [Member]
NAV %	21.20%	24.60%
Investment, Unaffiliated Issuer [Member] | Sustainability Segment [Member] | Warrant [Member]
NAV %	0.20%	0.20%

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