Cybersecurity Risk Management and Strategy Disclosure	12 Months Ended
Dec. 31, 2024
Cybersecurity Risk Management, Strategy, and Governance [Line Items]
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]	The Board established the Cyber Security Committee of the Board in December 2022 to augment the Board's oversight with cybersecurity focus and expertise and to complement the risk framework activities of the Enterprise Risk Management and Credit Policy Committee. The Cyber Security Committee considers risks associated with Horizon's overall cyber security and information technology programs; information technology audits; the security risk insurance that Horizon maintains for information technology, cyber security and privacy risks; Horizon's information security training programs; and compliance with all rules and regulations and risk control policies and procedures relating to information technology and cyber security. Pursuant to the Cyber Security Committee Charter, the Cyber Security Committee is required to meet at least three times per year and report to the Board annually. The Cyber Security Committee met three times in 2024. In addition, the Cyber Security Committee Charter provides that a majority of the Cyber Security Committee's voting members must qualify as independent directors under SEC rules and NASDAQ listing standards. During 2024, 3 of the Cyber Security Committee's members qualified as independent. Horizon's senior management briefs the Cyber Security Committee at each Cyber Security Committee meeting (see below for detailed discussion). In 2024, Horizon's information technology/cyber security program was audited by RSM and internal audit. The Cyber Security Committee Charter is posted on Horizon's website at www.horizonbank.com in the section headed “About Us – Investor Relations – Corporate Information” under the caption “Corporate Governance.” Through Horizon's enterprise risk management framework and reporting functions, the Board, its Committees and Management assess and manage cybersecurity risks created by cybersecurity threats. Horizon's Vice President, Information Security and Audit Information Security officer (“Information Security Officer”) provides an annual Information Security Program report to the Board and as needed when cybersecurity risk is elevated. Horizon's Senior Vice President, Senior Technology Officer is a member of the Cyber Security Committee and reports on cyber security risks at each meeting a minimum of three times a year. The Senior Vice President, Senior Technology Officer reports to the Executive Vice President, Senior Operations Officer, who also is a member of the Cyber Security Committee. For independence, the Information Security Officer reports to Horizon's Senior Vice President, Senior Auditor and Compliance Officer. Horizon's risk escalation framework requires progressive escalation of cyber security risks to Management and its Committees, then to Board Committees and, ultimately, to the Board.
Cybersecurity Risk Management Processes Integrated [Flag]	true
Cybersecurity Risk Management Processes Integrated [Text Block]	The Board established the Cyber Security Committee of the Board in December 2022 to augment the Board's oversight with cybersecurity focus and expertise and to complement the risk framework activities of the Enterprise Risk Management and Credit Policy Committee. The Cyber Security Committee considers risks associated with Horizon's overall cyber security and information technology programs; information technology audits; the security risk insurance that Horizon maintains for information technology, cyber security and privacy risks; Horizon's information security training programs; and compliance with all rules and regulations and risk control policies and procedures relating to information technology and cyber security.
Cybersecurity Risk Management Third Party Engaged [Flag]	true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag]	true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]	false
Cybersecurity Risk Board of Directors Oversight [Text Block]	Management's Operations Committee meets quarterly and provides oversight and governance of the technology and cyber security programs.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]	Management's Operations Committee meets quarterly and provides oversight and governance of the technology and cyber security programs.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]	Horizon's senior management briefs the Cyber Security Committee at each Cyber Security Committee meeting (see below for detailed discussion).
Cybersecurity Risk Role of Management [Text Block]	The Executive Vice President, Senior Operations Officer has 35 years of experience in operations and technology with an educational background in Business Administration. In the role of Senior Bank Operations Officer and Executive for the past 24 years, she oversees and works closely with Horizon's technology and security teams to develop and implement robust security measures to protect the Bank's systems, networks, and customer data. The Senior Bank Operations Officer stays current on the latest industry trends and emerging cyber threats through publications, webinars, seminars and banking association training around cyber security. She also collaborates with external agencies, such as law enforcement and regulatory bodies, to address cyber threats and ensure compliance with industry best practices. The Senior Vice President, Senior Technology Officer has 28 years of experience in information technology, with the last 13 as the information technology leader for the Bank. He holds a Bachelor's Degree in Computer Science. He is an active member of FS–ISAC's Mergers an Acquisition Working Group, and a named author of their 2023 “Cybersecurity Best Practices in Mergers, Acquisitions and Divestiture Deals” publication. He also serves as an advisory member of the Indiana Governor's Executive Council on Cybersecurity. He attends numerous industry training sessions including those put on by the SANS Institute, PaloAlto, Cisco, Microsoft, the Cybersecurity and Infrastructure Security Agency (CISA), and FS–ISAC. The Vice President, Information Security and Audit Information Security Officer has 28 years as an IT Professional, with the last 9 as the cybersecurity leader for Horizon Bank with an education background in Technology. He has achieved numerous certifications throughout his career including the Microsoft Certified Systems Engineer (MCSE) and Certified Novell Engineering (CNE 5/6) and has demonstrated a continued commitment to excellence and has attained certification as a Certified Information Systems Security Professional (CISSP) issued by ISC2 in 2022. Through continuous learning and professional development, the Information Security Officer has honed his expertise in cybersecurity frameworks, threat detection, incident response, and risk management. He also serves as a member of the Indiana Bankers Association (IBA) Cyber Security Committee and attends numerous industry training sessions including those put on by Microsoft, FS–ISAC, SANS Institute.
Cybersecurity Risk Management Positions or Committees Responsible [Flag]	true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block]	Horizon's Senior Vice President, Senior Technology Officer is a member of the Cyber Security Committee and reports on cyber security risks at each meeting a minimum of three times a year. The Senior Vice President, Senior Technology Officer reports to the Executive Vice President, Senior Operations Officer, who also is a member of the Cyber Security Committee. For independence, the Information Security Officer reports to Horizon's Senior Vice President, Senior Auditor and Compliance Officer. Horizon's risk escalation framework requires progressive escalation of cyber security risks to Management and its Committees, then to Board Committees and, ultimately, to the Board.
Cybersecurity Risk Management Expertise of Management Responsible [Text Block]	The Executive Vice President, Senior Operations Officer has 35 years of experience in operations and technology with an educational background in Business Administration. In the role of Senior Bank Operations Officer and Executive for the past 24 years, she oversees and works closely with Horizon's technology and security teams to develop and implement robust security measures to protect the Bank's systems, networks, and customer data. The Senior Bank Operations Officer stays current on the latest industry trends and emerging cyber threats through publications, webinars, seminars and banking association training around cyber security. She also collaborates with external agencies, such as law enforcement and regulatory bodies, to address cyber threats and ensure compliance with industry best practices. The Senior Vice President, Senior Technology Officer has 28 years of experience in information technology, with the last 13 as the information technology leader for the Bank. He holds a Bachelor's Degree in Computer Science. He is an active member of FS–ISAC's Mergers an Acquisition Working Group, and a named author of their 2023 “Cybersecurity Best Practices in Mergers, Acquisitions and Divestiture Deals” publication. He also serves as an advisory member of the Indiana Governor's Executive Council on Cybersecurity. He attends numerous industry training sessions including those put on by the SANS Institute, PaloAlto, Cisco, Microsoft, the Cybersecurity and Infrastructure Security Agency (CISA), and FS–ISAC. The Vice President, Information Security and Audit Information Security Officer has 28 years as an IT Professional, with the last 9 as the cybersecurity leader for Horizon Bank with an education background in Technology. He has achieved numerous certifications throughout his career including the Microsoft Certified Systems Engineer (MCSE) and Certified Novell Engineering (CNE 5/6) and has demonstrated a continued commitment to excellence and has attained certification as a Certified Information Systems Security Professional (CISSP) issued by ISC2 in 2022. Through continuous learning and professional development, the Information Security Officer has honed his expertise in cybersecurity frameworks, threat detection, incident response, and risk management. He also serves as a member of the Indiana Bankers Association (IBA) Cyber Security Committee and attends numerous industry training sessions including those put on by Microsoft, FS–ISAC, SANS Institute.
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]	The Senior Vice President, Senior Technology Officer and Information Security Officer are members of this committee and report monthly on the technology and cyber security programs. The Senior Vice President, Senior Technology Officer also is a member of Management's Enterprise Risk & Disclosure Committee, which meets a minimum of four times a year, to report on the technology and cyber security programs.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]	true

Cybersecurity Risk Management and Strategy Disclosure

12 Months Ended

Dec. 31, 2024

Cybersecurity Risk Management, Strategy, and Governance [Line Items]

Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]

The Board established the Cyber Security Committee of the Board in December 2022 to augment the Board's oversight with cybersecurity focus and expertise and to complement the risk framework activities of the Enterprise Risk Management and Credit Policy Committee. The Cyber Security Committee considers risks associated with Horizon's overall cyber security and information technology programs; information technology audits; the security risk insurance that Horizon maintains for information technology, cyber security and privacy risks; Horizon's information security training programs; and compliance with all rules and regulations and risk control policies and procedures relating to information technology and cyber security.

Pursuant to the Cyber Security Committee Charter, the Cyber Security Committee is required to meet at least three times per year and report to the Board annually. The Cyber Security Committee met three times in 2024. In addition, the Cyber Security Committee Charter provides that a majority of the Cyber Security Committee's voting members

must qualify as independent directors under SEC rules and NASDAQ listing standards. During 2024, 3 of the Cyber Security Committee's members qualified as independent.

Horizon's senior management briefs the Cyber Security Committee at each Cyber Security Committee meeting (see below for detailed discussion). In 2024, Horizon's information technology/cyber security program was audited by RSM and internal audit. The Cyber Security Committee Charter is posted on Horizon's website at www.horizonbank.com in the section headed “About Us – Investor Relations – Corporate Information” under the caption “Corporate Governance.”

Through Horizon's enterprise risk management framework and reporting functions, the Board, its Committees and Management assess and manage cybersecurity risks created by cybersecurity threats. Horizon's Vice President, Information Security and Audit Information Security officer (“Information Security Officer”) provides an annual Information Security Program report to the Board and as needed when cybersecurity risk is elevated. Horizon's Senior Vice President, Senior Technology Officer is a member of the Cyber Security Committee and reports on cyber security risks at each meeting a minimum of three times a year. The Senior Vice President, Senior Technology Officer reports to the Executive Vice President, Senior Operations Officer, who also is a member of the Cyber Security Committee. For independence, the Information Security Officer reports to Horizon's Senior Vice President, Senior Auditor and Compliance Officer. Horizon's risk escalation framework requires progressive escalation of cyber security risks to Management and its Committees, then to Board Committees and, ultimately, to the Board.

Cybersecurity Risk Management Processes Integrated [Flag]

true

Cybersecurity Risk Management Processes Integrated [Text Block]

Cybersecurity Risk Management Third Party Engaged [Flag]

true

Cybersecurity Risk Third Party Oversight and Identification Processes [Flag]

true

Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]

false

Cybersecurity Risk Board of Directors Oversight [Text Block]

Management's Operations Committee meets quarterly and provides oversight and governance of the technology and cyber security programs.

Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]

Management's Operations Committee meets quarterly and provides oversight and governance of the technology and cyber security programs.

Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]

Horizon's senior management briefs the Cyber Security Committee at each Cyber Security Committee meeting (see below for detailed discussion).

Cybersecurity Risk Role of Management [Text Block]

The Executive Vice President, Senior Operations Officer has 35 years of experience in operations and technology with an educational background in Business Administration. In the role of Senior Bank Operations Officer and Executive for the past 24 years, she oversees and works closely with Horizon's technology and security teams to develop and implement robust security measures to protect the Bank's systems, networks, and customer data. The Senior Bank Operations Officer stays current on the latest industry trends and emerging cyber threats through publications, webinars, seminars and banking association training around cyber security. She also collaborates with external agencies, such as law enforcement and regulatory bodies, to address cyber threats and ensure compliance with industry best practices.

The Senior Vice President, Senior Technology Officer has 28 years of experience in information technology, with the last 13 as the information technology leader for the Bank. He holds a Bachelor's Degree in Computer Science. He is an active member of FS–ISAC's Mergers an Acquisition Working Group, and a named author of their 2023 “Cybersecurity Best Practices in Mergers, Acquisitions and Divestiture Deals” publication. He also serves as an advisory member of the Indiana Governor's Executive Council on Cybersecurity. He attends numerous industry training sessions including those put on by the SANS Institute, PaloAlto, Cisco, Microsoft, the Cybersecurity and Infrastructure Security Agency (CISA), and FS–ISAC.

The Vice President, Information Security and Audit Information Security Officer has 28 years as an IT Professional, with the last 9 as the cybersecurity leader for Horizon Bank with an education background in Technology. He has achieved numerous certifications throughout his career including the Microsoft Certified Systems Engineer (MCSE) and Certified Novell Engineering (CNE 5/6) and has demonstrated a continued commitment to excellence and has attained certification as a Certified Information Systems Security Professional (CISSP) issued by ISC2 in 2022. Through continuous learning and professional development, the Information Security Officer has honed his expertise in cybersecurity frameworks, threat detection, incident response, and risk management. He also serves as a member of the Indiana Bankers Association (IBA) Cyber Security Committee and attends numerous industry training sessions including those put on by Microsoft, FS–ISAC, SANS Institute.

Cybersecurity Risk Management Positions or Committees Responsible [Flag]

true

Cybersecurity Risk Management Positions or Committees Responsible [Text Block]

Horizon's Senior Vice President, Senior Technology Officer is a member of the Cyber Security Committee and reports on cyber security risks at each meeting a minimum of three times a year. The Senior Vice President, Senior Technology Officer reports to the Executive Vice President, Senior Operations Officer, who also is a member of the Cyber Security Committee. For independence, the Information Security Officer reports to Horizon's Senior Vice President, Senior Auditor and Compliance Officer. Horizon's risk escalation framework requires progressive escalation of cyber security risks to Management and its Committees, then to Board Committees and, ultimately, to the Board.

Cybersecurity Risk Management Expertise of Management Responsible [Text Block]

Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]

The Senior Vice President, Senior Technology Officer and Information Security Officer are members of this committee and report monthly on the technology and cyber security programs. The Senior Vice President, Senior Technology Officer also is a member of Management's Enterprise Risk & Disclosure Committee, which meets a minimum of four times a year, to report on the technology and cyber security programs.

Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]

true