Pension (Schedule Of Net Periodic Pension Costs) (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Pension [Abstract]
Service cost	$ 90	$ 78
Interest cost	138	166
Expected return on plan assets	(279)	(268)
Recognized net actuarial loss	176	137
Net period cost	$ 125	$ 113	$ 459