Property, Net Of Accumulated Depreciation (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Property, Net Of Accumulated Depreciation
Land	$ 109,000,000		$ 109,000,000		$ 105,000,000
Buildings	3,879,000,000		3,879,000,000		3,692,000,000
Equipment	11,705,000,000		11,705,000,000		10,744,000,000
Construction in progress	1,662,000,000		1,662,000,000		822,000,000
Property, plant and equipment, gross	17,355,000,000		17,355,000,000		15,363,000,000
Accumulated depreciation	(7,089,000,000)		(7,089,000,000)		(6,420,000,000)
Total	10,266,000,000		10,266,000,000		8,943,000,000
Interest costs capitalized as part of property	11,000,000	5,000,000	28,000,000	12,000,000
Precious metals	2,300,000,000		2,300,000,000		2,000,000,000
Depletion expense	$ 6,000,000	$ 6,000,000	$ 16,000,000	$ 12,000,000