Earnings Per Share (Tables)

9 Months Ended

Sep. 30, 2012

Earnings Per Share [Abstract]

Components of basic and diluted shares used in EPS

A reconciliation of the components of basic and diluted shares used in the EPS calculation follows:

	Three Months Ended		Nine Months Ended
	September 30,		September 30,
	2012	2011	2012	2011
	(in millions)
Weighted-average basic common shares outstanding	177.9	176.6	177.6	176.5
Potential number of shares issuable upon excercise of in-the- money stock options under the Long-term Stock Incentive Plan	—	1.9	1.0	2.0
Average diluted common shares outstanding	177.9	178.5	178.6	178.5