Note 1 - Organization	6 Months Ended
Jun. 30, 2023
Notes to Financial Statements
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]	Note 1. Organization Horizon Technology Finance Corporation (the “Company”) was organized as a Delaware corporation on March 16, 2010 and is an externally managed, non-diversified, closed-end investment company. The Company has elected to be regulated as a business development company (“BDC”) under the 1940 Act. In addition, for tax purposes, the Company has elected to be treated as a regulated investment company (“RIC”) as defined under Subchapter M of the Internal Revenue Code of 1986, as amended (the “Code”). As a RIC, the Company generally is not subject to corporate-level federal income tax on the portion of its taxable income (including net capital gains) the Company distributes to its stockholders. The Company primarily makes secured debt investments to development-stage companies in the technology, life science, healthcare information and services and sustainability industries. All of the Company’s debt investments consist of loans secured by all of, or a portion of, the applicable debtor company’s tangible and intangible assets. On October 28, 2010, the Company completed an initial public offering (“IPO”) and its common stock trades on the Nasdaq Global Select Market under the symbol “HRZN”. Horizon Credit II LLC (“Credit II”) was formed as a Delaware limited liability company on June 28, 2011, with the Company as its sole equity member. Credit II is a special purpose bankruptcy-remote entity and is a separate legal entity from the Company. Any assets conveyed to Credit II are not available to creditors of the Company or any other entity other than Credit II’s lenders. The Company formed Horizon Funding 2019‑1 LLC (“2019‑1 LLC”) as a Delaware limited liability company on May 2, 2019 and Horizon Funding Trust 2019‑1 on May 15, 2019 (“2019‑1 Trust” and, together with the 2019‑1 LLC, the “2019‑1 Entities”). The 2019‑1 Entities are special purpose bankruptcy remote entities and are separate legal entities from the Company. The Company formed the 2019‑1 Entities for purposes of securitizing the 2019 Asset-Backed Notes. Horizon Funding I, LLC (“HFI”) was formed as a Delaware limited liability company on May 9, 2018, with Horizon Secured Loan Fund I LLC, a Delaware limited liability company (“HSLFI”) as its sole member. HFI is a special purpose bankruptcy-remote entity and is a separate legal entity from HSLFI. Any assets conveyed to HFI are not available to creditors of HSLFI or any other entity other than HFI’s lenders. As of April 21, 2020, HSLFI and its subsidiary, HFI, are consolidated by the Company. The Company formed Horizon Funding 2022‑1 LLC (“2022‑1 LLC”) as a Delaware limited liability company on September 30, 2022 and Horizon Funding Trust 2022‑1 on October 18, 2022 (“2022‑1 Trust” and, together with the 2022‑1 LLC, the “2022‑1 Entities”). The 2022‑1 Entities are special purpose bankruptcy remote entities and are separate legal entities from the Company. The Company formed the 2022‑1 Entities for purposes of securitizing the 2022 Asset-Backed Notes. The Company has established wholly owned subsidiaries, which are structured as Delaware limited liability companies, either to hold assets of portfolio companies acquired in connection with a foreclosure or bankruptcy or to hold equity in portfolio companies which the Company may control. Such wholly-owned subsidiaries are separate legal entities from the Company. The Company’s investment strategy is to maximize the investment portfolio’s return by generating current income from the debt investments the Company makes and capital appreciation from the warrants the Company receives when making such debt investments. The Company has entered into an investment management agreement (the “Investment Management Agreement”) with Horizon Technology Finance Management LLC (the “Advisor”) under which the Advisor manages the day-to-day operations of, and provides investment advisory services to, the Company.

Note 1 - Organization

6 Months Ended

Jun. 30, 2023

Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]

Note 1. Organization

Horizon Technology Finance Corporation (the “Company”) was organized as a Delaware corporation on March 16, 2010 and is an externally managed, non-diversified, closed-end investment company. The Company has elected to be regulated as a business development company (“BDC”) under the 1940 Act. In addition, for tax purposes, the Company has elected to be treated as a regulated investment company (“RIC”) as defined under Subchapter M of the Internal Revenue Code of 1986, as amended (the “Code”). As a RIC, the Company generally is not subject to corporate-level federal income tax on the portion of its taxable income (including net capital gains) the Company distributes to its stockholders. The Company primarily makes secured debt investments to development-stage companies in the technology, life science, healthcare information and services and sustainability industries. All of the Company’s debt investments consist of loans secured by all of, or a portion of, the applicable debtor company’s tangible and intangible assets.

On October 28, 2010, the Company completed an initial public offering (“IPO”) and its common stock trades on the Nasdaq Global Select Market under the symbol “HRZN”.

Horizon Credit II LLC (“Credit II”) was formed as a Delaware limited liability company on June 28, 2011, with the Company as its sole equity member. Credit II is a special purpose bankruptcy-remote entity and is a separate legal entity from the Company. Any assets conveyed to Credit II are not available to creditors of the Company or any other entity other than Credit II’s lenders.

The Company formed Horizon Funding 2019‑1 LLC (“2019‑1 LLC”) as a Delaware limited liability company on May 2, 2019 and Horizon Funding Trust 2019‑1 on May 15, 2019 (“2019‑1 Trust” and, together with the 2019‑1 LLC, the “2019‑1 Entities”). The 2019‑1 Entities are special purpose bankruptcy remote entities and are separate legal entities from the Company. The Company formed the 2019‑1 Entities for purposes of securitizing the 2019 Asset-Backed Notes.

Horizon Funding I, LLC (“HFI”) was formed as a Delaware limited liability company on May 9, 2018, with Horizon Secured Loan Fund I LLC, a Delaware limited liability company (“HSLFI”) as its sole member. HFI is a special purpose bankruptcy-remote entity and is a separate legal entity from HSLFI. Any assets conveyed to HFI are not available to creditors of HSLFI or any other entity other than HFI’s lenders. As of April 21, 2020, HSLFI and its subsidiary, HFI, are consolidated by the Company.

The Company formed Horizon Funding 2022‑1 LLC (“2022‑1 LLC”) as a Delaware limited liability company on September 30, 2022 and Horizon Funding Trust 2022‑1 on October 18, 2022 (“2022‑1 Trust” and, together with the 2022‑1 LLC, the “2022‑1 Entities”). The 2022‑1 Entities are special purpose bankruptcy remote entities and are separate legal entities from the Company. The Company formed the 2022‑1 Entities for purposes of securitizing the 2022 Asset-Backed Notes.

The Company has established wholly owned subsidiaries, which are structured as Delaware limited liability companies, either to hold assets of portfolio companies acquired in connection with a foreclosure or bankruptcy or to hold equity in portfolio companies which the Company may control. Such wholly-owned subsidiaries are separate legal entities from the Company.

The Company’s investment strategy is to maximize the investment portfolio’s return by generating current income from the debt investments the Company makes and capital appreciation from the warrants the Company receives when making such debt investments. The Company has entered into an investment management agreement (the “Investment Management Agreement”) with Horizon Technology Finance Management LLC (the “Advisor”) under which the Advisor manages the day-to-day operations of, and provides investment advisory services to, the Company.