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Stock-Based Compensation (Tables)
9 Months Ended
Sep. 30, 2011
Stock-Based Compensation [Abstract] 
Stock-Based Compensation Cost And Associated Tax Benefit
     Three Months Ended
September 30,
     Nine Months Ended
September 30,
 
     2011      2010      2011      2010  

Stock compensation cost

   $ 12.9      $ 13.6      $ 43.2      $ 41.3  

Tax benefit

   $ 5.0      $ 5.0      $ 16.2      $ 15.6  
Weighted Average Assumptions Used In Determining The Fair Value For Options Granted

Expected dividend yield

     1.53

Expected stock volatility

     41

Risk-free interest rate

     3.33

Expected holding period

     7.6 yrs   

Grant date fair value

   $ 12.49   
Stock Option Exercises And Restricted Stock Vesting