Earnings Per Share (Weighted Average Common And Common Equivalent Shares) (Details) In Millions | 3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2011 | Sep. 30, 2010 | Sep. 30, 2011 | Sep. 30, 2010 | |
| Earnings Per Share [Abstract] | ||||
| Weighted average common shares outstanding used in calculating basic earnings per share | 144.4 | 147.5 | 146.9 | 160.0 |
| Effect of dilutive stock-based awards | 2.6 | 2.1 | 2.6 | 1.4 |
| Weighted average common and common equivalent shares used in calculating diluted earnings per share | 147.0 | 149.6 | 149.5 | 161.4 |