Inventories (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Inventory [Line Items]
Raw materials	$ 1,719	$ 1,699
Work in process and other	861	883
Finished manufactured goods	3,296	3,187
Goods acquired for resale	4,001	3,906
Total inventory	$ 9,877	$ 9,675