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Consolidated Schedule of Investments (Unaudited) - Investments (Details) (Parentheticals)	Sep. 30, 2024	Dec. 31, 2023
NAV %	199.70%	218.90%
Investment, Affiliated Issuer, Controlled [Member]
NAV %	5.70%	4.40%
Investment, Affiliated Issuer, Noncontrolled [Member]
NAV %	2.40%	0.30%
Investment, Unaffiliated Issuer [Member]
NAV %	191.60%	214.20%
Unrestricted Short Term Investments [Member]
NAV %	9.10%	1.00%
Restricted Short Term Investments [Member]
NAV %	1.00%	0.80%
Debt Securities [Member] | Investment, Affiliated Issuer, Controlled [Member]
NAV %	2.00%
Debt Securities [Member] | Investment, Affiliated Issuer, Controlled [Member] | Consumer-related Technologies [Member]
NAV %		1.60%
Debt Securities [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Life Science [Member]
NAV %		0.30%
Debt Securities [Member] | Investment, Unaffiliated Issuer [Member]
NAV %	182.90%	205.00%
Debt Securities [Member] | Investment, Unaffiliated Issuer [Member] | Life Science [Member]
NAV %		75.60%
Debt Securities [Member] | Investment, Unaffiliated Issuer [Member] | Technology Sector [Member]
NAV %	56.70%	83.30%
Debt Securities [Member] | Investment, Unaffiliated Issuer [Member] | Life Science Segment [Member]
NAV %	76.00%
Debt Securities [Member] | Investment, Unaffiliated Issuer [Member] | Healthcare Information and Services Segment [Member]
NAV %	30.40%	21.50%
Debt Securities [Member] | Investment, Unaffiliated Issuer [Member] | Sustainability Segment [Member]
NAV %	19.80%	24.60%
Equity Securities [Member] | Investment, Affiliated Issuer, Controlled [Member]
NAV %	1.90%
Equity Securities [Member] | Investment, Affiliated Issuer, Controlled [Member] | Technology Sector [Member]
NAV %		0.90%
Equity Securities [Member] | Investment, Affiliated Issuer, Noncontrolled [Member]
NAV %	0.00%
Equity Securities [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Life Science [Member]
NAV %		0.00%
Equity Securities [Member] | Investment, Unaffiliated Issuer [Member]
NAV %	2.20%	1.50%
Warrant [Member] | Investment, Affiliated Issuer, Noncontrolled [Member]
NAV %	0.00%
Warrant [Member] | Investment, Affiliated Issuer, Noncontrolled [Member] | Life Science [Member]
NAV %		0.00%
Warrant [Member] | Investment, Unaffiliated Issuer [Member]
NAV %	5.50%	7.60%
Warrant [Member] | Investment, Unaffiliated Issuer [Member] | Technology Sector [Member]
NAV %	3.50%	4.50%
Warrant [Member] | Investment, Unaffiliated Issuer [Member] | Life Science Segment [Member]
NAV %	1.50%	2.30%
Warrant [Member] | Investment, Unaffiliated Issuer [Member] | Healthcare Information and Services Segment [Member]
NAV %	0.30%	0.60%
Warrant [Member] | Investment, Unaffiliated Issuer [Member] | Sustainability Segment [Member]
NAV %	0.20%	0.20%
Other Investments [Member] | Investment, Affiliated Issuer, Controlled [Member]
NAV %	1.80%
Other Investments [Member] | Investment, Affiliated Issuer, Controlled [Member] | Life Science [Member]
NAV %		1.90%
Other Investments [Member] | Investment, Affiliated Issuer, Noncontrolled [Member]
NAV %	2.40%
Other Investments [Member] | Investment, Unaffiliated Issuer [Member] | Life Science [Member]
NAV %		0.10%
Other Investments [Member] | Investment, Unaffiliated Issuer [Member] | Life Science Segment [Member]
NAV %	1.50%

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