v3.22.4
Cover - USD ($)
12 Months Ended
Dec. 31, 2022
Feb. 01, 2023
Jun. 30, 2022
Entity Listings [Line Items]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2022    
Entity File Number 1-10551    
Entity Registrant Name OMNICOM GROUP INC.    
Entity Incorporation, State or Country Code NY    
Entity Tax Identification Number 13-1514814    
Entity Address, Address Line One 280 Park Avenue    
Entity Address, City or Town New York    
Entity Address, State or Province NY    
Entity Address, Postal Zip Code 10017    
City Area Code 212    
Local Phone Number 415-3600    
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Large Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
ICFR Auditor Attestation Flag true    
Entity Shell Company false    
Entity Public Float     $ 12,846,357,000
Entity Common Stock, Shares Outstanding   202,713,338  
Entity Central Index Key 0000029989    
Current Fiscal Year End Date --12-31    
Document Fiscal Year Focus 2022    
Document Fiscal Period Focus FY    
Document Transition Report false    
Amendment Flag false    
Common Stock, $0.15 Par Value      
Entity Listings [Line Items]      
Title of 12(b) Security Common Stock, $0.15 Par Value    
Trading Symbol OMC    
Security Exchange Name NYSE    
0.800% Senior Notes due 2027      
Entity Listings [Line Items]      
Title of 12(b) Security 0.800% Senior Notes due 2027    
Trading Symbol OMC/27    
Security Exchange Name NYSE    
1.400% Senior Notes due 2031      
Entity Listings [Line Items]      
Title of 12(b) Security 1.400% Senior Notes due 2031    
Trading Symbol OMC/31    
Security Exchange Name NYSE    
£325 Million 2.25% Senior Notes due 2033      
Entity Listings [Line Items]      
Title of 12(b) Security 2.250% Senior Notes due 2033    
Trading Symbol OMC/33    
Security Exchange Name NYSE