Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Abstract]
Income from continuing operations	$ 40	$ 53
Income (loss) from discontinued operations, net of tax	0	0
Net income applicable to common shares	$ 40	$ 53
Weighted Average Number of Shares Outstanding, Diluted [Abstract]
Weighted average outstanding shares of common stock (in shares)	169.0	167.1
Dilutive effect of employee stock options and restricted stock (in shares)	2.6	3.9
Common stock and common stock equivalents (in shares)	171.6	171.0
Earnings Per Share, Basic [Abstract]
Basic earnings from continuing operations (in dollars per share)	$ 0.24	$ 0.32
Basic earnings from discontinued operations (in dollars per share)	$ 0.00	$ 0.00
Basic (in dollars per share)	$ 0.24us-gaap_EarningsPerShareBasic	$ 0.32us-gaap_EarningsPerShareBasic
Earnings Per Share, Diluted [Abstract]
Diluted earnings from continuing operations (in dollars per share)	$ 0.23	$ 0.31
Diluted earnings from discontinued operations (in dollars per share)	$ 0.00	$ 0.00
Diluted (in dollars per share)	$ 0.23us-gaap_EarningsPerShareDiluted	$ 0.31us-gaap_EarningsPerShareDiluted

After tax income (loss) from operations of a business component (exclusive of any gain (loss) on disposal, or provision therefore) during the reporting period, until its disposal.

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