XML 77 R80.htm IDEA: XBRL DOCUMENT v2.4.0.6
Income Taxes - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Income Taxes [Line Items]    
Income tax expense $ 78.5 $ 75.6
Effective tax rate 32.40% 31.90%