Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Earnings Per Share [Abstract]
Net income	$ 726	$ 942	$ 1,165	$ 1,623
Weighted-average shares outstanding	467,701,328	325,463,196	457,102,802	326,795,838
Share-based compensation plans	3,455,969	3,222,562	3,379,559	3,373,809
Weighted-average shares outstanding and assumed conversions	471,157,297	328,685,758	460,482,361	330,169,647
Basic earnings per share (US$ per share)	$ 1.55	$ 2.89	$ 2.55	$ 4.97
Diluted earnings per share (US$ per share)	$ 1.54	$ 2.86	$ 2.53	$ 4.91
Potential anti-dilutive share conversions	2,103,281	1,934,454	2,056,018	1,306,817