Earnings Per Share Components of Basic and Diluted Shares Used In EPS Calculation (Details) - shares shares in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share [Abstract]
Weighted-average basic common shares outstanding	176.7	180.1	176.5	180.0
Potential number of shares issuable upon exercise of in-the-money stock options under the Long-term Stock Incentive Plan	0.0	0.5	0.0	0.4
Average diluted common shares outstanding	176.7	180.6	176.5	180.4