Employee Benefits And Deferred Compensation Plans (Schedule Of Defined Benefit Plans Disclosures, SERP) (Details) - Supplemental Executive Retirement Plans [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Change in benefit obligation:
Benefit obligation at the beginning of the year	$ 4,349	$ 4,555
Service cost	188	194	$ 168
Interest cost	144	146	159
Actuarial (gain) loss	(234)	(354)
Benefits paid	(192)	(192)
Benefit obligation at the end of the year	4,255	4,349	4,555
Change in plan assets:
Fair value of plan assets at beginning of year
Actual return on plan assets
Employer contributions	192	192
Benefits paid	(192)	(192)
Fair value of plan assets at end of year
Funded status	(4,255)	(4,349)
Accrued benefit liabilities	(4,255)	(4,349)
Net actuarial loss	747	1,117
Prior service cost	187	218
Net amount recognized in equity – pre-tax	934	1,335
Net amount recognized on Consolidated Balance Sheets in Other Liabilities	(3,321)	(3,014)
Accumulated benefit obligation at year end	$ 3,902	$ 3,876