CONSOLIDATED BALANCE SHEET (Unaudited) (Parenthetical) (USD $) In Millions, except Share data, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Allowance for doubtful accounts	$ 163	$ 131
Inventories classified in Other assets	1,446	1,379
Accumulated depreciation	$ 17,475	$ 16,176
Common stock, par value	$ 0.50	$ 0.50
Common stock, shares authorized	6,500,000,000	6,500,000,000
Common stock, shares issued	3,577,103,522	3,577,103,522
Treasury stock, shares	532,699,267	536,109,713