List of principal companies included in the scope of consolidation during 2023 - Summary of Principal Companies and their Country of Incorporation (Details)	12 Months Ended
Dec. 31, 2023
Hoechst GmbH \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Deutschland GmbH \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
A. Nattermann & Cie. GmbH \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis GmbH \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Belgium \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Ablynx NV \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Genzyme Flanders BV \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi A/S \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis SA \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella Healthcare Spain, SL \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Oy \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis France \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Winthrop Industrie \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Recherche & Développement \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Groupe \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Chimie \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Participations \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Pasteur \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Aventis Pharma S.A. \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Biotechnology \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Mature IP \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Pasteur NVL \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Pasteur Europe \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
SECIPE SAS \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Pasteur Merieux SAS \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella Healthcare International SAS \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella Healthcare France SAS \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella Healthcare Group SAS \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Genzyme Polyclonals SAS \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis A.E.B.E. \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Private Co, Ltd \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	99.60%
Chinoin Private Co. Ltd \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	99.60%
Opella Healthcare Hungary Commercial K.F.T \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	99.60%
Opella Healthcare Hungary K.F.T \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	99.60%
Carraig Insurance DAC \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Genzyme Ireland Limited \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Holdings (Ireland) Ltd \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi SRL \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella Healthcare Italy SRL \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Genzyme Global Sarl \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Genzyme Luxembourg Sarl \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Norge AS \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi BV \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Foreign Participations BV \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Sp. z.o.o. \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella Healthcare Poland sp.z.o.o. \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Pasteur Sp. z.o.o. \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Produtos Farmaceuticos Lda \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis, s.r.o. \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella Healthcare Czech s.r.o \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Romania SRL \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella Healthcare Romania SRL \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis UK Holdings Limited \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Aventis Pharma Limited \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Synthelabo UK Ltd \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Aventis Pharma Holdings Ltd \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella Healthcare UK Limited \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
AO Sanofi Russia \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella Healthcare LLC \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi AB \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis (Suisse) SA \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Genzyme Global Sarl Baar Intellectual Property Branch \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Ilac Sanayi ve Ticaret AS \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Pasteur Asi Ticaret AS \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella Healthcare Tüketici Sağlığı Anonim Şirketi \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Saglik Urunleri Limited Sirketi \| Europe
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Genzyme Therapeutic Products Limited Partnership \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Aventis Inc. \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi US Services Inc. \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis U.S. LLC \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Chattem, Inc. \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Aventisub LLC \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Genzyme Corporation \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Pasteur Inc. \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
VaxServe, Inc. \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Bioverativ Inc. \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Bioverativ U.S. LLC \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Bioverativ Therapeutics Inc. \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Principia Biopharma Inc. \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Research Invest LLC \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Bioverativ Holdings LLC \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
RPR US Ltd. \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Kadmon Corporation, LLC \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Amunix \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Synthorx, Inc \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Provention Bio \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
QRIB Intermediate Holding \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
QRI \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
TargeGen Inc. \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Chattem (GB) Holding \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Translate Bio, Inc. \| United States
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis South Africa (Pty) Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Algérie \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Arabia Trading Company Limited \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Argentina SA \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Healthcare Pty Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Australia Pty Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Medley Farmaceutica Ltda \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella Healthcare Brazil Ltda. \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Canada Inc. \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Pasteur Limited \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Merieux Canada Holdings ULC (Canada) \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi (Hangzhou) Pharmaceuticals Co., Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi (China) Investment Co., Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi (Beijing) Pharmaceuticals Co.Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Pasteur Biologies Co., Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Shenzhen Sanofi pasteur Biological Products Co, Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Shanghai Rongheng Pharmaceutical Co, Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis de Colombia SA \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Korea Co. Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Pasteur Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella healthcare Korea Inc. \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Gulf FZE \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Egypt \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	99.80%
Sanofi Hong-Kong Limited \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi India Limited \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	60.40%
Sanofi Healthcare India Private Limited \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	99.90%
Sanofi-Aventis Israël Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi K.K. \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
SSP Co.,Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis (Malaysia) SDN. BHD. \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Maroc \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis de Mexico SA de CV \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Pasteur SA de CV \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Azteca Vacunas, SA de CV \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis de Panama SA \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella Healthcare Panama SA \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Puerto Rico Inc \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Philippines Inc. \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Opella Healthcare Philippines Inc. \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Singapore Pte. Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Aventis Pharma (Manufacturing) Pte. Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Manufacturing Pte Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Taiwan Co., Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis (Thailand) Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Pasteur Ltd \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis de Venezuela SA \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi-Aventis Vietnam Company Limited \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	100.00%
Sanofi Vietnam Shareholding Company Limited \| Other countries
Disclosure of subsidiaries [line items]
Financial interest in principal fully consolidated companies	85.00%