Weighted Average Shares Outstanding (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted average shares outstanding - basic	1,321.7	1,351.9
Weighted Average Number Diluted Shares Outstanding Adjustment	27.5	0
Weighted average shares outstanding - assuming dilution	1,349.2	1,351.9
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount		12.8
Stock Issued During Period, Shares, New Issues	10	8
Treasury Stock, Shares, Acquired	10	13
Payments for repurchase of common stock, rounded	$ 125	$ 100
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	12.0	48.0