Retirement Plans (Amounts Recognized On The Consolidated Balance Sheet) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Current liabilities	$ (275)	$ (254)
Noncurrent liabilities	(4,627)	(3,596)
Pension Benefits [Member]
Noncurrent assets	110	106
Current liabilities	(90)	(72)
Noncurrent liabilities	(4,012)	(3,022)
Net liability recognized	(3,992)	(2,988)
Other Post-Retirement Benefits [Member]
Current liabilities	(185)	(182)
Noncurrent liabilities	(615)	(574)
Net liability recognized	$ (800)	$ (756)