Employee Benefits (Amounts Recognized in Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Retirement Income Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss	$ 112,532	$ 109,215
Prior service benefit	(16,942)	(20,410)
Total	95,590	88,805
Other Pension Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss	9,300	11,408
Prior service benefit	(107)	(146)
Total	$ 9,193	$ 11,262