Capital Stock (Tables)
 9 Months Ended
Sep. 30, 2012
Weighted Average Number of Shares Outstanding Reconciliation [Abstract]  
Schedule Of Weighted Average Number Of Shares [Table Text Block]
   Three Months Nine Months 
   Ended September 30, Ended September 30, 
 (In millions)2012 2011 2012 2011 
           
 Weighted-average shares:        
  Basic (a) 48.5  48.0  48.4  47.8 
  Effect of dilutive stock options and awards 0.1  0.1  0.2  0.3 
  Diluted 48.6  48.1  48.6  48.1 
           
 Antidilutive stock options and awards excluded from denominator 2.2  2.7  2.5  2.2