Annual report pursuant to Section 13 and 15(d)

SEGMENT INFORMATION (Financial Information by Geographic Area) (Detail)

v2.4.1.9
SEGMENT INFORMATION (Financial Information by Geographic Area) (Detail) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 12 Months Ended
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Dec. 31, 2013
Sep. 30, 2013
Jun. 30, 2013
Mar. 31, 2013
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Revenues from External Customers and Long-Lived Assets [Line Items]                      
Operating revenue $ 624.6us-gaap_SalesRevenueServicesNet $ 613.4us-gaap_SalesRevenueServicesNet $ 613.9us-gaap_SalesRevenueServicesNet $ 584.5us-gaap_SalesRevenueServicesNet $ 578.5us-gaap_SalesRevenueServicesNet $ 572.0us-gaap_SalesRevenueServicesNet $ 586.9us-gaap_SalesRevenueServicesNet $ 566.5us-gaap_SalesRevenueServicesNet $ 2,436.4us-gaap_SalesRevenueServicesNet $ 2,303.9us-gaap_SalesRevenueServicesNet $ 2,073.0us-gaap_SalesRevenueServicesNet
Percentage of operating revenues                 100.00%efx_PercentageOfConsolidatedOperatingRevenues 100.00%efx_PercentageOfConsolidatedOperatingRevenues 100.00%efx_PercentageOfConsolidatedOperatingRevenues
Long-lived assets 4,069.1us-gaap_NoncurrentAssets       3,891.5us-gaap_NoncurrentAssets       4,069.1us-gaap_NoncurrentAssets 3,891.5us-gaap_NoncurrentAssets  
Percentage of consolidated long-lived assets                 100.00%efx_PercentageOfLongLivedAssets 100.00%efx_PercentageOfLongLivedAssets  
U.S.                      
Revenues from External Customers and Long-Lived Assets [Line Items]                      
Operating revenue                 1,810.2us-gaap_SalesRevenueServicesNet
/ us-gaap_StatementGeographicalAxis
= country_US 		1,766.0us-gaap_SalesRevenueServicesNet
/ us-gaap_StatementGeographicalAxis
= country_US 		1,561.9us-gaap_SalesRevenueServicesNet
/ us-gaap_StatementGeographicalAxis
= country_US
Percentage of operating revenues                 74.00%efx_PercentageOfConsolidatedOperatingRevenues
/ us-gaap_StatementGeographicalAxis
= country_US 		77.00%efx_PercentageOfConsolidatedOperatingRevenues
/ us-gaap_StatementGeographicalAxis
= country_US 		76.00%efx_PercentageOfConsolidatedOperatingRevenues
/ us-gaap_StatementGeographicalAxis
= country_US
Long-lived assets 3,286.1us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= country_US 		      3,332.8us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= country_US 		      3,286.1us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= country_US 		3,332.8us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= country_US 		 
Percentage of consolidated long-lived assets                 81.00%efx_PercentageOfLongLivedAssets
/ us-gaap_StatementGeographicalAxis
= country_US 		86.00%efx_PercentageOfLongLivedAssets
/ us-gaap_StatementGeographicalAxis
= country_US 		 
Canada                      
Revenues from External Customers and Long-Lived Assets [Line Items]                      
Operating revenue                 154.2us-gaap_SalesRevenueServicesNet
/ us-gaap_StatementGeographicalAxis
= stpr_CA 		155.6us-gaap_SalesRevenueServicesNet
/ us-gaap_StatementGeographicalAxis
= stpr_CA 		153.9us-gaap_SalesRevenueServicesNet
/ us-gaap_StatementGeographicalAxis
= stpr_CA
Percentage of operating revenues                 6.00%efx_PercentageOfConsolidatedOperatingRevenues
/ us-gaap_StatementGeographicalAxis
= stpr_CA 		7.00%efx_PercentageOfConsolidatedOperatingRevenues
/ us-gaap_StatementGeographicalAxis
= stpr_CA 		7.00%efx_PercentageOfConsolidatedOperatingRevenues
/ us-gaap_StatementGeographicalAxis
= stpr_CA
Long-lived assets 55.8us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= stpr_CA 		      54.7us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= stpr_CA 		      55.8us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= stpr_CA 		54.7us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= stpr_CA 		 
Percentage of consolidated long-lived assets                 1.00%efx_PercentageOfLongLivedAssets
/ us-gaap_StatementGeographicalAxis
= stpr_CA 		1.00%efx_PercentageOfLongLivedAssets
/ us-gaap_StatementGeographicalAxis
= stpr_CA 		 
U.K.                      
Revenues from External Customers and Long-Lived Assets [Line Items]                      
Operating revenue                 217.0us-gaap_SalesRevenueServicesNet
/ us-gaap_StatementGeographicalAxis
= country_GB 		144.7us-gaap_SalesRevenueServicesNet
/ us-gaap_StatementGeographicalAxis
= country_GB 		133.5us-gaap_SalesRevenueServicesNet
/ us-gaap_StatementGeographicalAxis
= country_GB
Percentage of operating revenues                 9.00%efx_PercentageOfConsolidatedOperatingRevenues
/ us-gaap_StatementGeographicalAxis
= country_GB 		6.00%efx_PercentageOfConsolidatedOperatingRevenues
/ us-gaap_StatementGeographicalAxis
= country_GB 		6.00%efx_PercentageOfConsolidatedOperatingRevenues
/ us-gaap_StatementGeographicalAxis
= country_GB
Long-lived assets 371.9us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= country_GB 		      122.3us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= country_GB 		      371.9us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= country_GB 		122.3us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= country_GB 		 
Percentage of consolidated long-lived assets                 9.00%efx_PercentageOfLongLivedAssets
/ us-gaap_StatementGeographicalAxis
= country_GB 		3.00%efx_PercentageOfLongLivedAssets
/ us-gaap_StatementGeographicalAxis
= country_GB 		 
Other                      
Revenues from External Customers and Long-Lived Assets [Line Items]                      
Operating revenue                 255.0us-gaap_SalesRevenueServicesNet
/ us-gaap_StatementGeographicalAxis
= efx_OtherCountriesMember 		237.6us-gaap_SalesRevenueServicesNet
/ us-gaap_StatementGeographicalAxis
= efx_OtherCountriesMember 		223.7us-gaap_SalesRevenueServicesNet
/ us-gaap_StatementGeographicalAxis
= efx_OtherCountriesMember
Percentage of operating revenues                 11.00%efx_PercentageOfConsolidatedOperatingRevenues
/ us-gaap_StatementGeographicalAxis
= efx_OtherCountriesMember 		10.00%efx_PercentageOfConsolidatedOperatingRevenues
/ us-gaap_StatementGeographicalAxis
= efx_OtherCountriesMember 		11.00%efx_PercentageOfConsolidatedOperatingRevenues
/ us-gaap_StatementGeographicalAxis
= efx_OtherCountriesMember
Long-lived assets $ 355.3us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= efx_OtherCountriesMember 		      $ 381.7us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= efx_OtherCountriesMember 		      $ 355.3us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= efx_OtherCountriesMember 		$ 381.7us-gaap_NoncurrentAssets
/ us-gaap_StatementGeographicalAxis
= efx_OtherCountriesMember 		 
Percentage of consolidated long-lived assets                 9.00%efx_PercentageOfLongLivedAssets
/ us-gaap_StatementGeographicalAxis
= efx_OtherCountriesMember 		10.00%efx_PercentageOfLongLivedAssets
/ us-gaap_StatementGeographicalAxis
= efx_OtherCountriesMember