Loans And Allowance For Loan Losses (Summary Of Activity In The Allowance For Loan Losses) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	$ 152,132	$ 153,532	$ 151,532	$ 156,532
Provision	9,216	6,757	18,655	11,177
Loans charged off	12,645	12,705	25,935	25,005
Less recoveries on loans	5,129	3,948	9,580	8,828
Net loan charge-offs (recoveries)	7,516	8,757	16,355	16,177
Balance at end of period	153,832	151,532	153,832	151,532
Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	86,027	88,906	82,086	89,622
Provision	1,569	(2,361)	5,720	(4,113)
Loans charged off	661	1,408	2,174	2,132
Less recoveries on loans	2,263	1,192	3,566	2,952
Net loan charge-offs (recoveries)	(1,602)	216	(1,392)	(820)
Balance at end of period	89,198	86,329	89,198	86,329
Personal Banking Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Balance at beginning of period	66,105	64,626	69,446	66,910
Provision	7,647	9,118	12,935	15,290
Loans charged off	11,984	11,297	23,761	22,873
Less recoveries on loans	2,866	2,756	6,014	5,876
Net loan charge-offs (recoveries)	9,118	8,541	17,747	16,997
Balance at end of period	$ 64,634	$ 65,203	$ 64,634	$ 65,203