Revenue Recognition Of Non-Interest Income (Schedule Of Disaggregation Of Insurance Service And Other Fees) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disaggregation of Revenue [Line Items]
Total insurance service and other fees	$ 3,215	$ 2,169	$ 7,132	$ 6,249
Commercial Property And Casualty Insurance Commissions [Member]
Disaggregation of Revenue [Line Items]
Total insurance service and other fees	1,330	1,090	2,665	2,334
Personal Property And Casualty Insurance Commissions [Member]
Disaggregation of Revenue [Line Items]
Total insurance service and other fees	917	637	2,249	2,022
Employee Benefits Sales Commissions [Member]
Disaggregation of Revenue [Line Items]
Total insurance service and other fees	241	200	664	398
Profit Sharing And Contingent Revenue [Member]
Disaggregation of Revenue [Line Items]
Total insurance service and other fees	486	28	790	777
Wealth Management And Other Financial Services [Member]
Disaggregation of Revenue [Line Items]
Total insurance service and other fees	151	110	462	321
Insurance Claims Services Revenue [Member]
Disaggregation of Revenue [Line Items]
Total insurance service and other fees	65	89	234	338
Other Insurance-Related Revenue [Member]
Disaggregation of Revenue [Line Items]
Total insurance service and other fees	$ 25	$ 15	$ 68	$ 59