Stockholders' Equity (Stock Options Included in and Excluded from Calculations) (Details)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Stockholders' Equity Note [Abstract]      
Stock options included in the calculation of EPS (dilutive) 0.9 4.4 6.5