Acquisition and Restructuring Costs (Activity Related To Restructuring-Related Accruals) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2012	$ 262
Accruals for Business Operations and Information Technology Transformation program	8
Adjustments of accruals for 2012 expense control measures	(9)
Payments and adjustments	(57)
Balance as of March 31, 2013	204
Employee- Related Costs
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2012	195
Accruals for Business Operations and Information Technology Transformation program	9
Adjustments of accruals for 2012 expense control measures	(9)
Payments and adjustments	(44)
Balance as of March 31, 2013	151
Real Estate Consolidation
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2012	49
Accruals for Business Operations and Information Technology Transformation program	0
Adjustments of accruals for 2012 expense control measures	0
Payments and adjustments	(6)
Balance as of March 31, 2013	43
Information Technology Costs
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2012	5
Accruals for Business Operations and Information Technology Transformation program	(1)
Adjustments of accruals for 2012 expense control measures	0
Payments and adjustments	(4)
Balance as of March 31, 2013	0
Asset and Other Write-Offs
Restructuring Reserve [Roll Forward]
Balance as of December 31, 2012	13
Accruals for Business Operations and Information Technology Transformation program	0
Adjustments of accruals for 2012 expense control measures	0
Payments and adjustments	(3)
Balance as of March 31, 2013	$ 10