Acquisition And Restructuring Costs (Activity Related To Restructuring-Related Accruals) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012
Business Acquisition [Line Items]
Beginning balance	$ 287
Additional restructuring accruals other	15
Accruals for expense control measures	(7)
Payments and adjustments	(77)
Ending balance	218
Employee-Related Costs [Member]
Business Acquisition [Line Items]
Beginning balance	162
Additional restructuring accruals other	0
Accruals for expense control measures	3
Payments and adjustments	(37)
Ending balance	128
Real Estate Consolidation [Member]
Business Acquisition [Line Items]
Beginning balance	39
Additional restructuring accruals other	3
Accruals for expense control measures	0
Payments and adjustments	(1)
Ending balance	41
Information Technology Costs [Member]
Business Acquisition [Line Items]
Beginning balance	33
Additional restructuring accruals other	12
Accruals for expense control measures	0
Payments and adjustments	(11)
Ending balance	34
Fixed-Income Trading Portfolio [Member]
Business Acquisition [Line Items]
Beginning balance	38
Additional restructuring accruals other	0
Accruals for expense control measures	(10)
Payments and adjustments	(24)
Ending balance	4
Asset And Other Write Offs [Member]
Business Acquisition [Line Items]
Beginning balance	15
Additional restructuring accruals other	0
Accruals for expense control measures	0
Payments and adjustments	(4)
Ending balance	$ 11