Earnings Per Share (Tables)

9 Months Ended

Sep. 30, 2011

Earnings Per Share [Abstract]

Weighted Average Common And Common Equivalent Shares

	Three Months Ended		Nine Months Ended
	September 30,		September 30,
	2011	2010	2011	2010
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

Anti-Dilutive Options Excluded From The Computation Of Diluted Earnings Per Share

	Three Months Ended		Nine Months Ended
	September 30,		September 30,
	2011	2010	2011	2010
Anti-dilutive options excluded from the computation of diluted earnings per share	0.4	0.5	0.4	3.7