Loans And Allowance For Loan Losses (Summary Of Activity In The Allowance For Loan Losses) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	$ 181,532	$ 194,538	$ 184,532	$ 197,538
Provision	5,215	12,188	13,380	27,977
Loans charged off	17,020	19,602	32,937	42,991
Less recoveries on loans	8,806	4,414	13,558	9,014
Net loans charged off	8,214	15,188	19,379	33,977
Balance at end of period	178,533	191,538	178,533	191,538
Commercial [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	117,474	128,351	122,497	119,946
Provision	(4,448)	1,815	(7,646)	15,280
Loans charged off	3,179	3,946	5,707	10,310
Less recoveries on loans	4,824	1,043	5,527	2,347
Net loans charged off	(1,645)	2,903	180	7,963
Balance at end of period	114,671	127,263	114,671	127,263
Personal Banking [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	64,058	66,187	62,035	77,592
Provision	9,663	10,373	21,026	12,697
Loans charged off	13,841	15,656	27,230	32,681
Less recoveries on loans	3,982	3,371	8,031	6,667
Net loans charged off	9,859	12,285	19,199	26,014
Balance at end of period	$ 63,862	$ 64,275	$ 63,862	$ 64,275