Note 10 - Concentrations of Credit Risk	12 Months Ended
Dec. 31, 2025
Notes to Financial Statements
Concentration Risk Disclosure [Text Block]	Note *10.* Concentrations of credit risk The Company’s debt investments consist primarily of loans to development-stage companies at various stages of development in the technology, life science, healthcare information and services and sustainability industries. Many of these companies may have relatively limited operating histories and also may experience variation in operating results. Many of these companies conduct business in regulated industries and could be affected by changes in government regulations. Most of the Company’s borrowers will need additional capital to satisfy their continuing working capital needs and other requirements, and in many instances, to service the interest and principal payments on the loans. The Company’s largest debt investments may vary from year to year as new debt investments are recorded and existing debt investments are repaid. The Company’s five largest debt investments at cost represented 26% and 22% of total debt investments outstanding as of December 31, 2025 and 2024, respectively. The Company’s five largest debt investments at fair value represented 26% and 23% of total debt investments outstanding as of December 31, 2025 and 2024, respectively. No single debt investment represented more than 10% of the total debt investments at cost or fair value as of December 31, 2025 or 2024. Investment income, consisting of interest and fees, can fluctuate significantly upon repayment of large debt investments. Interest income from the five largest debt investments at cost accounted for 22%, 19% and 17% of total interest and fee income on investments for the years ended December 31, 2025, 2024 and 2023, respectively. Interest income from the five largest debt investments at fair value accounted for 23%, 19% and 15% of total interest and fee income on investments for the years ended December 31, 2025, 2024 and 2023, respectively.

Note 10 - Concentrations of Credit Risk

12 Months Ended

Dec. 31, 2025

Concentration Risk Disclosure [Text Block]

Note 10. Concentrations of credit risk

The Company’s debt investments consist primarily of loans to development-stage companies at various stages of development in the technology, life science, healthcare information and services and sustainability industries. Many of these companies may have relatively limited operating histories and also may experience variation in operating results. Many of these companies conduct business in regulated industries and could be affected by changes in government regulations. Most of the Company’s borrowers will need additional capital to satisfy their continuing working capital needs and other requirements, and in many instances, to service the interest and principal payments on the loans.

The Company’s largest debt investments may vary from year to year as new debt investments are recorded and existing debt investments are repaid. The Company’s five largest debt investments at cost represented 26% and 22% of total debt investments outstanding as of December 31, 2025 and 2024, respectively. The Company’s five largest debt investments at fair value represented 26% and 23% of total debt investments outstanding as of December 31, 2025 and 2024, respectively. No single debt investment represented more than 10% of the total debt investments at cost or fair value as of December 31, 2025 or 2024. Investment income, consisting of interest and fees, can fluctuate significantly upon repayment of large debt investments. Interest income from the five largest debt investments at cost accounted for 22%, 19% and 17% of total interest and fee income on investments for the years ended December 31, 2025, 2024 and 2023, respectively. Interest income from the five largest debt investments at fair value accounted for 23%, 19% and 15% of total interest and fee income on investments for the years ended December 31, 2025, 2024 and 2023, respectively.

- Definition

The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.

+ References

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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Horizon Technology Finance Corp 10-K