Parent Company Financial Information (Condensed Statements Of Condition) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Condensed Financial Statements, Captions [Line Items]
Other assets	$ 76,333	$ 64,029
Total assets	4,105,210	3,710,340
Long-term borrowings, net of issuance costs of $869 and $939, respectively	39,131	39,061
Other liabilities	28,528	24,503
Shareholders' equity	381,177	320,054	$ 293,844	$ 279,532
Total liabilities and shareholders' equity	4,105,210	3,710,340
Debt issuance costs	869	939
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Cash and due from subsidiary	10,687	16,516
Investment in and receivables due from subsidiary	409,127	344,741
Other assets	5,901	4,020
Total assets	425,715	365,277
Long-term borrowings, net of issuance costs of $869 and $939, respectively	39,131	39,061
Other liabilities	5,407	6,162
Shareholders' equity	381,177	320,054
Total liabilities and shareholders' equity	425,715	365,277
Debt issuance costs	$ 869	$ 939