Employee Benefit Plans (Schedule of Change in Projected Benefit Obligation) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Pension Benefit Plan [Member]
Change in Projected Benefit Obligation:
Beginning Balance	$ 83,927	$ 88,013
Service Cost	2,171	2,426	$ 2,399
Interest Cost	3,426	3,061	3,143
Actuarial (Gain) Loss	14,188	(7,018)
Benefits Paid	(2,821)	(2,555)
Ending Balance	100,891	83,927	88,013
Other Benefits Plan [Member]
Change in Projected Benefit Obligation:
Beginning Balance	48,474	54,345
Service Cost	839	1,135	1,089
Interest Cost	1,984	1,898	1,964
Actuarial (Gain) Loss	4,671	(8,160)
Benefits Paid	(802)	(744)
Ending Balance	$ 55,166	$ 48,474	$ 54,345