Basic and Diluted Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Earnings Per Share [Abstract]
Income from Continuing Operations	$ 192	$ 358	$ 392	$ 590
Weighted Average Number of Shares Outstanding, Basic (in shares)	361	359	361	358
Incremental Shares from Assumed Conversion of Dilutive Stock Options, Restricted Stock and Shares of Common Stock in Rabbi Trust (in shares)	5	4	4	4
Weighted Average Number of Shares Outstanding, Diluted (in shares)	366	363	365	362
Earnings from Continuing Operations Per Share, Basic (in dollars per share)	$ 0.53	$ 1.00	$ 1.09	$ 1.64
Earnings from Continuing Operations Per Share, Diluted (in dollars per share)	$ 0.52	$ 0.99	$ 1.07	$ 1.63
Number of antidilutive stock options, shares of restricted stock and shares of common stock in rabbi trust excluded from calculation above (in shares)	3	5	4	5