Allowance For Loan Losses (Schedule Of Non-Commercial Loans By Payment Performance) (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Recorded Investment [Line Items]
Total	$ 2,877,117	$ 2,862,534
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	1,395,670	1,383,133
Residential Real Estate [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	1,392,531	1,379,797
Residential Real Estate [Member] | Nonperforming [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	3,139	3,336
Home equity - junior lien [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	142,694	147,036
Home equity - junior lien [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	142,523	146,877
Home equity - junior lien [Member] | Nonperforming [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	171	159
Consumer Loan [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	34,754	36,083
Consumer Loan [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	34,754	36,049
Consumer Loan [Member] | Nonperforming [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	0	34
Demand Deposit Account Overdrafts [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	2,825	3,361
Demand Deposit Account Overdrafts [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	2,825	3,361
Demand Deposit Account Overdrafts [Member] | Nonperforming [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	0	0
Noncommercial Loans [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	1,575,943	1,569,613
Noncommercial Loans [Member] | Performing [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	1,572,633	1,566,084
Noncommercial Loans [Member] | Nonperforming [Member]
Financing Receivable, Recorded Investment [Line Items]
Total	$ 3,310	$ 3,529