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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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