Equifax Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

COMMITMENTS AND CONTINGENCIES - Additional Information (Details)

COMMITMENTS AND CONTINGENCIES - Additional Information (Details) customer in Thousands	1 Months Ended	3 Months Ended				9 Months Ended	12 Months Ended	13 Months Ended
	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) office	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) claim	Sep. 30, 2018 USD ($) office	Dec. 31, 2017 USD ($) claim plaintiff customer	Sep. 30, 2018 USD ($) office
Commitments and Contingencies Disclosure [Line Items]
Accruals related to guarantees and indemnities \| $		$ 0			$ 0	$ 0	$ 0	$ 0
Indian Tribes and Nations
Commitments and Contingencies Disclosure [Line Items]
Pending claims \| claim					2		2
Maximum
Commitments and Contingencies Disclosure [Line Items]
Debt instrument, term (or less)						1 year
United States
Commitments and Contingencies Disclosure [Line Items]
Pending claims \| claim					1,000		1,000
Number of plaintiffs \| plaintiff							2,500
Pending individual arbitration claims \| claim					50		50
Pending putative class action claims \| claim					19		19
Canada
Commitments and Contingencies Disclosure [Line Items]
Pending claims \| claim					7		7
Pending national class actions \| claim					5		5
Georgia
Commitments and Contingencies Disclosure [Line Items]
Pending claims \| claim					4		4
Number of claims combined into a single claim \| claim							3
Cybersecurity Incident
Commitments and Contingencies Disclosure [Line Items]
Number of customers impacted \| customer							145,500
Cybersecurity incident remediation, legal, and other professional costs \| $	$ 87,500,000		$ 0	$ 4,100,000	$ 76,500,000
Insurance recoveries \| $		$ 0				$ 45,000,000		$ 95,000,000
Number of state attorneys general offices company is in cooperation with \| office		48				48		48
Cybersecurity Incident \| United States and Canada
Commitments and Contingencies Disclosure [Line Items]
Number of customers, credit card information accessed \| customer							209
Cybersecurity Incident \| United States
Commitments and Contingencies Disclosure [Line Items]
Number of customers, personal information accessed \| customer							182
Number of customers, name and partial driver's license information stolen \| customer							2,400
Cybersecurity Incident \| Canada
Commitments and Contingencies Disclosure [Line Items]
Number of customers, personal information accessed \| customer							19
Cybersecurity Incident \| United Kingdom
Commitments and Contingencies Disclosure [Line Items]
Number of customers, personal information accessed \| customer							860
Free Credit File Monitoring And Identity Theft Protection Offering
Commitments and Contingencies Disclosure [Line Items]
Cybersecurity incident remediation, legal, and other professional costs \| $							$ 50,700,000
Free Credit File Monitoring And Identity Theft Protection Offering \| Selling, General and Administrative Expenses
Commitments and Contingencies Disclosure [Line Items]
Cybersecurity incident remediation, legal, and other professional costs \| $		$ 7,800,000				$ 11,900,000
Investigation, Remediation, Legal, And Other Professional Services
Commitments and Contingencies Disclosure [Line Items]
Cybersecurity incident remediation, legal, and other professional costs \| $							$ 113,300,000
Insurance coverage \| $						125,000,000
Insurance coverage deductible \| $						$ 7,500,000.0
Multi-State Investigation
Commitments and Contingencies Disclosure [Line Items]
Number of state attorneys general offices company is in cooperation with \| office		46				46		46