Basic and Diluted Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Earnings Per Share [Abstract]
Income from Continuing Operations	$ 200	$ 232
Weighted Average Number of Shares Outstanding, Basic (in shares)	360	358
Incremental Shares from Assumed Conversion of Dilutive Stock Options, Restricted Stock and Shares of Common Stock in Rabbi Trust (in shares)	5	4
Weighted Average Number of Shares Outstanding, Diluted (in shares)	365	362
Earnings from Continuing Operations Per Share, Basic (in dollars per share)	$ 0.56	$ 0.65
Earnings from Continuing Operations Per Share, Diluted (in dollars per share)	$ 0.55	$ 0.64
Number of antidilutive stock options, shares of restricted stock and shares of common stock in rabbi trust excluded from calculation above (in shares)	6	5