Quarterly report pursuant to Section 13 or 15(d)

Changes in Amount of Goodwill (Detail)

v2.4.0.6
Changes in Amount of Goodwill (Detail) (USD $)
In Millions, unless otherwise specified
9 Months Ended
Sep. 30, 2012
Goodwill [Line Items]  
Balance, December 31, 2011 $ 1,961.2
Acquisitions 4.1
Adjustments to initial purchase price allocation 0.2
Foreign currency translation 10.2
Tax benefits of stock options exercised (1.2)
Balance, September 30, 2012 1,974.5
U.S. Consumer Information Solutions [Member]
 
Goodwill [Line Items]  
Balance, December 31, 2011 638.4
Acquisitions 0
Adjustments to initial purchase price allocation 0
Foreign currency translation 0
Tax benefits of stock options exercised 0
Balance, September 30, 2012 638.4
International [Member]
 
Goodwill [Line Items]  
Balance, December 31, 2011 348.5
Acquisitions 4.1
Adjustments to initial purchase price allocation 0
Foreign currency translation 10.0
Tax benefits of stock options exercised 0
Balance, September 30, 2012 362.6
Workforce Solutions [Member]
 
Goodwill [Line Items]  
Balance, December 31, 2011 935.0
Acquisitions 0
Adjustments to initial purchase price allocation 0.2
Foreign currency translation 0
Tax benefits of stock options exercised (1.2)
Balance, September 30, 2012 934.0
North America Personal Solutions [Member]
 
Goodwill [Line Items]  
Balance, December 31, 2011 1.8
Acquisitions 0
Adjustments to initial purchase price allocation 0
Foreign currency translation 0
Tax benefits of stock options exercised 0
Balance, September 30, 2012 1.8
North America Commercial Solutions [Member]
 
Goodwill [Line Items]  
Balance, December 31, 2011 37.5
Acquisitions 0
Adjustments to initial purchase price allocation 0
Foreign currency translation 0.2
Tax benefits of stock options exercised 0
Balance, September 30, 2012 $ 37.7