Pensions and Other Postretirement Benefit Plans (Schedule of Amounts That Will Be Amortized from Accumulated Other Comprehensive Income) (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Pension Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Actuarial loss	$ 2,409
Prior service cost/(benefit)	32
Total	2,441
Other postretirement benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Actuarial loss	2,592
Prior service cost/(benefit)	(4,488)
Total	$ (1,896)