Loans And Leases (Net Loans) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011	Mar. 31, 2011	Dec. 31, 2010
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 12,275	$ 10,053
Allowance for loan losses	(22)	(22)	(80)	(100)
Loans and leases, net of allowance for loan losses	12,253	10,031
Institutional [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	11,815	9,593
Allowance for loan losses	(22)	(22)	(31)	(31)
Institutional [Member] | U.S. [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Investment funds	7,502	5,592
Commercial and financial	923	563
Purchased receivables	408	563
Lease financing	393	397
Institutional [Member] | Non-U.S. [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Investment funds	1,000	796
Commercial and financial	404	453
Purchased receivables	336	372
Lease financing	849	857
Commercial Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	460	460
Allowance for loan losses	0		(49)	(69)
Commercial Real Estate [Member] | U.S. [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial real estate	$ 460	$ 460