Earnings Per Share and Share Repurchases (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Income from continuing operations	$ 53	$ 62
Income (loss) from discontinued operations, net of tax	0	(1)
Net income applicable to common shares	$ 53	$ 61
Weighted Average Number of Shares Outstanding, Diluted [Abstract]
Weighted average outstanding shares of common stock	167.1	163.7
Dilutive effect of employee stock options and restricted stock	3.9	3.8
Common stock and common stock equivalents	171.0	167.5
Earnings Per Share, Basic [Abstract]
Basic earnings from continuing operations (in dollars per share)	$ 0.32	$ 0.38
Basic earnings from discontinued operations (in dollars per share)	$ 0.00	$ (0.01)
Basic (in dollars per share)	$ 0.32	$ 0.37
Earnings Per Share, Diluted [Abstract]
Diluted earnings from continuing operations (in dollars per share)	$ 0.31	$ 0.37
Diluted earnings from discontinued operations (in dollars per share)	$ 0.00	$ (0.01)
Diluted (in dollars per share)	$ 0.31	$ 0.36
Employee Stock Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	0	0