Shareholders' Equity (Details) - USD ($)	3 Months Ended		6 Months Ended		39 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Nov. 30, 2014	Apr. 30, 2012
Common Stock Programs
Total cost of shares purchased			$ 550,000,000
Weighted average shares outstanding
Shares for basic earnings per share (in shares)	284,500,000	298,500,000	284,300,000	301,000,000
Common stock equivalents (in shares)	2,200,000	3,100,000	2,600,000	3,400,000
Shares for diluted earnings per share (in shares)	286,700,000	301,600,000	286,900,000	304,400,000
Number of shares excluded from the calculation of diluted earnings per share	0	0
2012 - Share Repurchase Program [Member]
Common Stock Programs
Share repurchase authorization limit							$ 5,000,000,000.0
Shares purchased (in shares)	3,000,000	7,400,000	5,500,000	14,600,000	67,600,000
Average price per share of stock repurchased	$ 100.92	$ 87.67	$ 100.57	$ 85.59
Total cost of shares purchased	$ 300,000,000	$ 650,000,000	$ 550,000,000	$ 1,300,000,000	$ 4,900,000,000
Share repurchase, remaining authorization limit	$ 5,100,000,000		$ 5,100,000,000		$ 5,100,000,000
Share Repurchase Program of 2014 [Member]
Common Stock Programs
Share repurchase authorization limit						$ 5,000,000,000.0