Commitments and Contingencies (Schedule of Remaining Contractual Loan Commitments by Class) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2012
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loan Commitments	$ 5,578,342	$ 4,151,541	$ 4,094,181
Commercial Loan
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loan Commitments	3,521,227	2,431,023	2,406,226
Total consumer
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loan Commitments	$ 2,057,115	$ 1,720,518	$ 1,687,955