Acquisition And Restructuring Costs (Activity Related To Restructuring-Related Accruals) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Business Acquisition [Line Items]
Beginning balance	$ 137
Additional restructuring-related accruals	133	156
Accruals for expense control measures	120
Payments	(103)	(19)
Ending balance	287	137
Employee-Related Costs [Member]
Business Acquisition [Line Items]
Beginning balance	90
Additional restructuring-related accruals	85	105
Accruals for expense control measures	62
Payments	(75)	(15)
Ending balance	162	90
Real Estate Consolidation [Member]
Business Acquisition [Line Items]
Beginning balance	47
Additional restructuring-related accruals	7	51
Payments	(15)	(4)
Ending balance	39	47
Information Technology Costs [Member]
Business Acquisition [Line Items]
Additional restructuring-related accruals	41
Payments	(8)
Ending balance	33
Trading Portfolio [Member]
Business Acquisition [Line Items]
Accruals for expense control measures	38
Ending balance	38
Asset And Other Write-Offs [Member]
Business Acquisition [Line Items]
Accruals for expense control measures	20
Payments	(5)
Ending balance	$ 15