Employee Benefit Plans (Schedule Of Changes In Plan Assets And Benefit Obligations Recognized In Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Retirement Benefits [Abstract]
Net loss	$ 82	$ 1,719	$ 1,276
Amortization of net loss	(1,475)	(1,552)	(1,423)
Total recognized in other comprehensive (income) loss	(1,393)	167	(147)
Total recognized in net periodic benefit cost and other comprehensive (income) loss	213	$ 2,103	$ 1,262
Defined benefit plan, estimated amortization of net loss in next fiscal year	$ 1,100