Loans and Leases (Net Loans) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 13,486,000,000	$ 12,307,000,000
Allowance for loan losses	(28,000,000)	(22,000,000)
Loans and leases, net of allowance for loan losses	13,458,000,000	12,285,000,000
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	209,000,000	411,000,000
Institutional
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	13,277,000,000	11,896,000,000
U.S. | Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial real estate	209,000,000	411,000,000
U.S. | Institutional
Accounts, Notes, Loans and Financing Receivable [Line Items]
Investment funds	8,695,000,000	8,376,000,000
Commercial and financial	1,372,000,000	613,000,000
Purchased receivables	217,000,000	276,000,000
Lease financing	339,000,000	380,000,000
Non-U.S. | Institutional
Accounts, Notes, Loans and Financing Receivable [Line Items]
Investment funds	1,718,000,000	829,000,000
Commercial and financial	154,000,000	520,000,000
Purchased receivables	26,000,000	118,000,000
Lease financing	$ 756,000,000	$ 784,000,000