Derivatives And Other Financial Instruments (Gain Or Loss On Hedged Items) (Details) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	$ (95)	$ 144	$ (20)	$ 86
Amount of Gain or (Loss) Recognized in Earnings on Hedged Items	97	(109)	51	(59)
Sales [Member] | Aluminum Contracts [Member]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	(100)	101	(78)	7
Amount of Gain or (Loss) Recognized in Earnings on Hedged Items	102	(94)	76	(8)
Interest Expense [Member] | Interest Rate Contracts [Member]
Amount of Gain or (Loss) Recognized in Earnings on Derivatives	5	43	58	79
Amount of Gain or (Loss) Recognized in Earnings on Hedged Items	$ (5)	$ (15)	$ (25)	$ (51)