Earnings Per Share (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Earnings Per Share [Abstract]
Income from Continuing Operations Used for Diluted Earnings Per Share Calculation	$ 1,214		$ 907		$ 965
Dilutive Securities, Effect on Basic Earnings Per Share	(17)	[1]	0	[1]	0	[1]
Income (Loss) from Continuing Operations available to common stockholders, diluted	$ 1,197		$ 907		$ 965
Weighted Average Number of Shares Outstanding, Basic (in shares)	361		359		356
Incremental Shares From Assumed Conversion of Dilutive Stock Options and Restricted Stock (in shares)	6		4		3
Weighted Average Number of Shares Outstanding, Diluted (in shares)	367		363		359
Earnings from Continuing Operations Per Share, Basic (in dollars per share)	$ 3.36		$ 2.53		$ 2.71
Earnings from Continuing Operations Per Share, Diluted (in dollars per share)	$ 3.27		$ 2.50		$ 2.68
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares)	3		3		5
Weighted average Exercise Price of antidilutive options (in dollars per share)	$ 60.30		$ 53.40		$ 48.73

[1] Consistent with GAAP, when dilutive, deferred compensation gains or losses, net of tax, are excluded from net income while our common shares held in the rabbi trust are included in the diluted share count. For this reason, the diluted earnings per share calculations for the year ended December 31, 2014 excludes deferred compensation gains, net of tax.