Cybersecurity Risk Management and Strategy Disclosure	12 Months Ended
Cybersecurity Risk Management and Strategy Disclosure	Dec. 31, 2025
Cybersecurity Risk Management, Strategy, and Governance [Line Items]
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]	Cybersecurity Risk Management and Strategy We have developed and implemented a cybersecurity risk management program intended to protect the confidentiality, integrity, and availability of our critical systems and information. We use the National Institute of Standards and Technology Cybersecurity Framework, or NIST CSF, and the ISO 27001 framework as published by the International Organization for Standardization as guides to help us identify, assess, and manage cybersecurity risks relevant to our business. This does not imply that we meet any particular technical standards, specifications, or requirements, only that we use such standards as a guide. Our cybersecurity risk management program is integrated into our overall enterprise risk management program; and shares common methodologies, reporting channels, and governance processes that apply across the enterprise risk management program to other legal, compliance, strategic, operational, and financial risk areas. Key aspects of our cybersecurity risk management program include, but are not limited to, the following: •risk assessments designed to help identify risks from cybersecurity threats to our critical systems, and information; •an internal security staff principally responsible for managing our cybersecurity risk assessment processes, our security controls, and our response to cybersecurity incidents; •the use of external service providers, where appropriate, to assess, test, or otherwise assist with aspects of our security processes; •cybersecurity awareness training of our employees, incident response personnel, and senior management; •a cybersecurity incident response plan that includes procedures for responding to cybersecurity incidents; and •a third-party risk management process for key service providers and suppliers based on our assessment of their criticality to our operations and respective risk profile. While we have experienced cybersecurity incidents that resulted in the disruption of our information technology systems and required us to engage third parties to remediate the issues, we have not identified risks from known cybersecurity threats, including as a result of any prior cybersecurity incidents, that have materially affected or are reasonably likely to materially affect us, including our operations, results of operations, or financial condition. We face certain ongoing risks from cybersecurity threats that, if realized, are reasonably likely to materially affect us, including our business, results of operations and financial condition. See Item 1A, “Risk Factors - We rely extensively on information technology systems and data, and cybersecurity incidents could adversely affect us.”
Cybersecurity Risk Management Processes Integrated [Flag]	true
Cybersecurity Risk Management Processes Integrated [Text Block]	Our cybersecurity risk management program is integrated into our overall enterprise risk management program; and shares common methodologies, reporting channels, and governance processes that apply across the enterprise risk management program to other legal, compliance, strategic, operational, and financial risk areas. Key aspects of our cybersecurity risk management program include, but are not limited to, the following: •risk assessments designed to help identify risks from cybersecurity threats to our critical systems, and information; •an internal security staff principally responsible for managing our cybersecurity risk assessment processes, our security controls, and our response to cybersecurity incidents; •the use of external service providers, where appropriate, to assess, test, or otherwise assist with aspects of our security processes; •cybersecurity awareness training of our employees, incident response personnel, and senior management; •a cybersecurity incident response plan that includes procedures for responding to cybersecurity incidents; and •a third-party risk management process for key service providers and suppliers based on our assessment of their criticality to our operations and respective risk profile.
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 Committee or Subcommittee Responsible for Oversight [Text Block]	Our Board of Directors, or Board, considers cybersecurity risk as part of its risk oversight function and has delegated to its Audit Committee oversight of cybersecurity and other information technology risks. Our Audit Committee oversees management’s ongoing activities related to our cybersecurity risk management program.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]	Our Audit Committee receives periodic reports from management on our cybersecurity risks. In addition, management updates the Audit Committee, where it deems appropriate, regarding cybersecurity incidents it considers to be significant. Our Audit Committee reports to the full Board regarding its activities, including those related to cybersecurity. The full Board also receives briefings from management on our cybersecurity risk management program. Board members receive presentations on cybersecurity topics from our Chief Information Officer, or CIO, Chief Information Security Officer, or CISO, and Chief Information Risk Officer, or CIRO, and other security staff as part of the Board’s continuing education on topics that impact the Company.
Cybersecurity Risk Role of Management [Text Block]	Our management team, including our CIO, CISO and CIRO, is responsible for assessing and managing our material risks from cybersecurity threats. Our CIO has over 25 years of experience in global IT operations, including developing information security strategy, managing enterprise risk and overseeing digital transformation initiatives. Our CISO has over 20 years of experience leading global information security, cyber risk, and compliance programs. His expertise spans Security Operations Center (SOC) leadership, security architecture, incident response, information and third‑party risk, compliance management, and data protection, supported by leading certifications including CISSP, CISM, CISA, and CRISC. Our CIRO has extensive experience in enterprise risk management, governance, and compliance. He has over 30 years of experience leading the development of risk management frameworks, management of cyber security and cyber regulatory compliance. He holds the following professional certifications: CISA, CISM, CPA and Chartered Accountant (SA). The team has primary responsibility for our overall cybersecurity risk management program and supervises both our internal cybersecurity personnel and our retained external cybersecurity advisors. Our Information Technology management team collectively holds over 50 years of strategic IT and global transformational experience, including having held IT advisory roles with top-tier organizations. Each member of the team has experience operating in complex, international business environments. The IT management team has demonstrated achievement in Information Security strategy development, risk management and implementation of security and risk management programs that drive awareness, decrease exposure and strengthen organizational IT controls. Our management team is informed about and monitors the prevention, detection, mitigation, and remediation of key cybersecurity risks and incidents through various means, which may include briefings from internal security personnel, threat intelligence and other information obtained from governmental, public or private sources, including external advisors engaged by us, and alerts and reports produced by security tools deployed in the IT environment.
Cybersecurity Risk Management Positions or Committees Responsible [Flag]	true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block]	Our management team, including our CIO, CISO and CIRO, is responsible for assessing and managing our material risks from cybersecurity threats.
Cybersecurity Risk Management Expertise of Management Responsible [Text Block]	Our Information Technology management team collectively holds over 50 years of strategic IT and global transformational experience, including having held IT advisory roles with top-tier organizations. Each member of the team has experience operating in complex, international business environments. The IT management team has demonstrated achievement in Information Security strategy development, risk management and implementation of security and risk management programs that drive awareness, decrease exposure and strengthen organizational IT controls.
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]	Our management team is informed about and monitors the prevention, detection, mitigation, and remediation of key cybersecurity risks and incidents through various means, which may include briefings from internal security personnel, threat intelligence and other information obtained from governmental, public or private sources, including external advisors engaged by us, and alerts and reports produced by security tools deployed in the IT environment.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]	true

OMNICOM GROUP INC. 10-K