Pensions and Other Postretirement Benefit Plans (Schedule of Amounts That Will Be Amortized from Accumulated Other Comprehensive Income) (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Actuarial loss	$ 2,254
Prior service cost/(benefit)	68
Total	2,322
Other postretirement benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Actuarial loss	2,226
Prior service cost/(benefit)	(4,488)
Total	$ (2,262)