Document and Entity Information Document - USD ($)
12 Months Ended
Dec. 31, 2019
Feb. 13, 2020
Jun. 28, 2019
DEI [Abstract]      
Document Annual Report true    
Document Information [Line Items]      
Document Type 10-K    
Document Period End Date Dec. 31, 2019    
Document Transition Report false    
Entity File Number 1-6686    
Entity Incorporation, State or Country Code DE    
Entity Tax Identification Number 13-1024020    
Entity Address, Address Line One 909 Third Avenue,    
Entity Address, City or Town New York,    
Entity Address, State or Province NY    
Entity Address, Postal Zip Code 10022    
City Area Code (212)    
Local Phone Number 704-1200    
Title of 12(b) Security Common Stock, par value $0.10 per share    
Trading Symbol IPG    
Security Exchange Name NYSE    
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    
Entity Shell Company false    
Entity Common Stock, Shares Outstanding   387,824,443  
Entity Central Index Key 0000051644    
Current Fiscal Year End Date --12-31    
Amendment Flag false    
Document Fiscal Year Focus 2019    
Document Fiscal Period Focus FY    
Entity Public Float     $ 8,700,000,000