Inventories (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Inventories [Line Items]
Raw materials	$ 1,734	$ 1,598
Work in process and other	941	897
Finished manufactured goods	3,207	3,114
Goods acquired for resale	3,594	3,366
Total inventory	$ 9,476	$ 8,975