Employee Benefit Plans (Schedule Of Changes In The Benefit Obligation, The Plan Assets, The Funded Status Of Pension Plans And Components Of Net Periodic Benefit Costs) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Change in Projected Benefit Obligation:
Benefit obligation at beginning of year	$ 52,975	$ 49,715
Service cost	1,223	1,277	$ 1,252
Interest cost	2,123	2,078	1,899
Actuarial loss (gain)	4,502	1,976
Benefit payments	(1,825)	(2,071)
Benefit obligation at end of year	58,998	52,975	49,715
Change in Plan Assets:
Fair value of plan assets at beginning of year	45,498	42,341
Actual return on plan assets	7,635	3,228
Employer contributions	2,500	2,000
Benefit payments	(1,825)	(2,071)
Fair value of plan assets at end of year	53,808	45,498	$ 42,341
Unfunded status at end of year (included in accounts payable and accrued expenses in 2017 and 2016)	(5,190)	(7,477)
Accumulated benefit obligation	58,860	52,824
Net loss recognized in accumulated other comprehensive loss	$ 15,135	$ 16,528