Annual report pursuant to Section 13 and 15(d)

Cover Page

Cover Page - USD ($)
12 Months Ended
Dec. 31, 2020
Jan. 29, 2021
Jun. 30, 2020
Cover [Abstract]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2020    
Current Fiscal Year End Date --12-31    
Document Transition Report false    
Entity File Number 001-06605    
Entity Registrant Name EQUIFAX INC.    
Entity Incorporation, State or Country Code GA    
Entity Tax Identification Number 58-0401110    
Entity Address, Address Line One 1550 Peachtree Street    
Entity Address, Address Line Two N.W.    
Entity Address, City or Town Atlanta    
Entity Address, State or Province GA    
Entity Address, Postal Zip Code 30309    
City Area Code 404    
Local Phone Number 885-8000    
Title of 12(b) Security Common Stock, $1.25 par value per share    
Trading Symbol EFX    
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    
ICFR Auditor Attestation Flag true    
Entity Shell Company false    
Entity Public Float     $ 20,875,342,327
Entity Common Stock, Shares Outstanding   121,788,082  
Documents Incorporated by Reference Portions of Registrant’s definitive proxy statement for its 2021 annual meeting of shareholders are incorporated by reference in Part III of this Form 10-K.    
Amendment Flag false    
Document Fiscal Year Focus 2020    
Document Fiscal Period Focus FY    
Entity Central Index Key 0000033185