Inventories (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Inventories [Line Items]
Raw materials	$ 1,687	$ 1,598
Work in process and other	916	897
Finished manufactured goods	3,234	3,114
Goods acquired for resale	3,218	3,366
Total inventory	$ 9,055	$ 8,975