v3.8.0.1
Earnings Per Share (Details) - USD ($)
$ / shares in Units, shares in Millions, $ in Millions
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Earnings Per Share Details [Abstract]        
Net income $ 1,194 $ 1,131 $ 3,434 $ 3,089
Weighted-Average Number Of Shares Outstanding        
Basic 794.5 829.0 803.4 836.8
Dilutive effect of stock options 1.7 1.6 1.7 1.4
Dilutive effect of retention shares and units 1.4 1.6 1.4 1.4
Diluted 797.6 832.2 806.5 839.6
Earnings per share - basic $ 1.50 $ 1.36 $ 4.27 $ 3.69
Earnings per share - diluted $ 1.50 $ 1.36 $ 4.26 $ 3.68
Stock options excluded as their inclusion would be anti-dilutive 1.9 0.9 1.8 2.4