Employee Benefit Plans (Schedule of Employee Benefit Plans Recognized in Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Noncurrent Liability	$ 36,139	$ 36,515
Pension Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Current Liability	373	327
Noncurrent Liability	18,858	19,284
Net Liability Recognized	19,231	19,611
Other Benefits Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Current Liability
Noncurrent Liability	17,281	17,231
Net Liability Recognized	$ 17,281	$ 17,231