Loans and Leases (Schedule of Allowance for Loan Losses) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases, Individually evaluated for impairment	$ 206		$ 422
Loans and leases, Collectively evaluated for impairment	13,280	[1]	11,885	[1]
Total loans and leases	13,486		12,307
Institutional
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases, Individually evaluated for impairment	26		11
Loans and leases, Collectively evaluated for impairment	13,251	[1]	11,885	[1]
Total loans and leases	13,277		11,896
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans and leases, Individually evaluated for impairment	180		411
Loans and leases, Collectively evaluated for impairment	29	[1]	0	[1]
Total loans and leases	$ 209		$ 411

[1] As of December 31, 2013 and 2012, all of the allowance for loan losses of $28 million and $22 million, respectively, related to institutional loans collectively evaluated for impairment.