| Cover | Jul. 20, 2022 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Jul. 20, 2022 |
| Entity Registrant Name | EQUIFAX INC. |
| Entity Central Index Key | 0000033185 |
| Amendment Flag | false |
| Entity Incorporation, State or Country Code | GA |
| Entity File Number | 001-06605 |
| 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 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
