Hercules Capital, Inc. Quarterly report [Sections 13 or 15(d)]

Quarterly report [Sections 13 or 15(d)]

Investments - Narrative (Details)

Investments - Narrative (Details)	Sep. 30, 2025 portfolioCompany equityInvestment	Dec. 31, 2024 equityInvestment portfolioCompany
Schedule Of Investments [Line Items]
Percentage of fair value investment in portfolio companies	28.90%	31.60%
Count greater five percent fair value equity \| equityInvestment	4	3
Percentage of equity investments held in portfolio companies	57.00%	49.70%
Concentrations of Credit Risk
Schedule Of Investments [Line Items]
Number of portfolio companies \| portfolioCompany	7	6

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details