Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Share data	Jun. 30, 2011	Dec. 31, 2010
Consolidated Balance Sheets
Doubtful accounts and allowances	$ 24	$ 20
Accumulated depreciation	$ 6,824	$ 6,420
Common stock, par value	$ 0.50	$ 0.50
Common stock, shares authorized	3,800,000,000	3,800,000,000
Common stock, shares issued	1,634,000,000	1,626,000,000
Treasury stock, at cost, shares held	66,000,000	65,000,000