Allowance for Loan and Lease Losses and Unfunded Loan Commitments and Letters of Credit (Changes in the Allowance for Unfunded Commitments and Letters of Credit) (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Allowance for Loan and Lease Losses [Roll Forward]
Beginning Balance	$ 54,057	$ 59,748	$ 60,993	$ 53,478
Provision charged to expense	500	9,000	2,650	37,500
Loans charged off	(4,872)	(7,540)	(16,653)	(31,466)
Recoveries	737	1,126	3,432	2,822
Ending balance	50,422	62,334	50,422	62,334
Beginning balance	1,460	815	1,165	775
Net changes in the allowance for unfunded commitments and letters of credit	0	350	295	390
Ending balance	$ 1,460	$ 1,165	$ 1,460	$ 1,165