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

Quarterly report [Sections 13 or 15(d)]

Cover
- COVER
Financial Statements
Notes to Financial Statements
Accounting Policies
- Summary of Significant Accounting Policies (Policies)
Notes Tables
Notes Details

Subsequent Events (Details)

v3.26.1

Subsequent Events (Details) $ / shares in Units, $ in Thousands				3 Months Ended				12 Months Ended
	May 14, 2026 $ / shares	Feb. 25, 2026 $ / shares	Feb. 04, 2026 $ / shares	Dec. 31, 2026 $ / shares	Sep. 30, 2026 $ / shares	Jun. 30, 2026 USD ($) quarterlyDistribution $ / shares	Mar. 31, 2026 $ / shares	Dec. 31, 2026 $ / shares	Jul. 27, 2026 $ / shares	Jul. 24, 2026 USD ($)	Dec. 31, 2025 USD ($)
Subsequent Event [Line Items]
Supplemental dividends amount to be paid (in dollars per share)			$ 0.28
Dividends, number of quarterly distributions \| quarterlyDistribution						4
Total Available \| $						$ 2,968,294					$ 2,782,136
Subsequent Event
Subsequent Event [Line Items]
Dividend payable per share (in dollars per share)									$ 0.21
Subsequent Event \| July 2031 Notes
Subsequent Event [Line Items]
Total Available \| $										$ 325,000
Debt instrument, interest rate										6.30%
O 2026 Q2 Dividends \| Subsequent Event
Subsequent Event [Line Items]
Dividend payable per share (in dollars per share)									0.40
S 2026 A Dividends \| Subsequent Event \| Forecast
Subsequent Event [Line Items]
Supplemental dividends amount to be paid (in dollars per share)								$ 0.28
S 2026 Q1 Dividends
Subsequent Event [Line Items]
Supplemental dividends amount to be paid each quarter (in dollars per share)							$ 0.07
Dividends paid (in dollars per share)		$ 0.07
S 2026 Q2 Dividends
Subsequent Event [Line Items]
Supplemental dividends amount to be paid each quarter (in dollars per share)						$ 0.07
Dividends paid (in dollars per share)	$ 0.07
S 2026 Q3 Dividends \| Subsequent Event
Subsequent Event [Line Items]
Dividend payable per share (in dollars per share)									$ 0.07
S 2026 Q3 Dividends \| Subsequent Event \| Forecast
Subsequent Event [Line Items]
Supplemental dividends amount to be paid each quarter (in dollars per share)					$ 0.07
S 2026 Q4 Dividends \| Subsequent Event \| Forecast
Subsequent Event [Line Items]
Supplemental dividends amount to be paid each quarter (in dollars per share)				$ 0.07

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