Net Periodic Benefit Costs (Schedule Of Net Periodic Benefit Cost) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Pension [Member]
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 50	$ 55	$ 151	$ 165
Expected return on plan assets	(81)	(70)	(244)	(208)
Amortization of the net loss	25	24	76	72
Net periodic (benefit) cost	(6)	9	(17)	29
Supplemental Executive Retirement Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	38	37	116	109
Interest cost	38	51	114	151
Amortization of prior service cost	7	7	23	23
Amortization of the net loss	88	58	263	176
Net periodic (benefit) cost	$ 171	$ 153	$ 516	$ 459