Asset Impairment, Exit And Implementation Costs (Movement In The Severance Liability And Details Of Asset Impairment And Exit Costs) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2012
Restructuring Cost and Reserve [Line Items]
Severance liability balance, December 31, 2011	$ 156
Charges	47
Cash spent	(106)
Other	(29)
Severance liability balance, September 30, 2012	68
Severance [Member]
Restructuring Cost and Reserve [Line Items]
Severance liability balance, December 31, 2011	156
Charges	0
Cash spent	(88)
Other	0
Severance liability balance, September 30, 2012	68
Other [Member]
Restructuring Cost and Reserve [Line Items]
Charges	47
Cash spent	(18)
Other	$ (29)