Business Segments (Schedule Of Revenue And Long-Lived Assets, By Geographical Area) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Consolidated revenue	$ 14,529		$ 14,272		$ 12,731
Consolidated long-lived assets	48,532		45,487		43,604
U.S. [Member]
Consolidated revenue	13,062		13,068		11,573
Consolidated long-lived assets	45,920		42,754		41,043
Latin America [Member]
Consolidated revenue	1,467	[1]	1,204	[1]	1,158	[1]
Consolidated long-lived assets	$ 2,612	[1]	$ 2,733	[1]	$ 2,561	[1]

[1] Change in amounts of long-lived assets in Latin America is primarily due to foreign currency translation adjustments on property, plant and equipment and other long-lived asset balances.