Allowance For Loan Losses (Schedule Of Credit Quality Indicators) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment [Line Items]
Total	$ 3,083,767	$ 3,046,226
Commercial Industrial Loans And Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	1,454,165	1,415,183
Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	197,429	185,667
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	1,256,736	1,229,516
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	1,403,718	1,355,111
Pass [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	189,029	176,823
Pass [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	1,214,689	1,178,288
Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	10,054	18,458
Special Mention [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	742	2,427
Special Mention [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	9,312	16,031
Substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	40,393	41,614
Substandard [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	7,658	6,417
Substandard [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	32,735	35,197
Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	0	0
Doubtful [Member] | Commercial And Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	0	0
Doubtful [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	$ 0	$ 0