Employee Benefit Plans (Schedule of Employee Benefit Plans Recognized in Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Noncurrent Liability	$ 34,671	$ 30,661
Pension Benefit Plan [Member]
Current Liability	393	347
Noncurrent Liability	20,118	16,809
Net Liability Recognized	20,511	17,156
Other Benefits Plan [Member]
Current Liability
Noncurrent Liability	14,553	13,852
Net Liability Recognized	$ 14,553	$ 13,852