Pension Plan (Components Of Net Periodic Benefit Expense) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 1,317	$ 1,264	$ 2,634	$ 2,528
Interest cost	1,271	1,217	2,542	2,434
Expected return on plan assets	(2,863)	(2,737)	(5,726)	(5,474)
Amortization of prior service cost	0	0	0	0
Recognized net actuarial loss	144	193	288	386
Benefit expense	(131)	(63)	(262)	(126)
Pension plan contributions	$ 0	$ 0	$ 0	$ 0