Accumulated Other Comprehensive Income (Loss) (Components of OCI) (Details 1) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before tax		$ (1,502)	$ (38,063)
Other Comprehensive Income (Loss), income tax		299	120
Other Comprehensive Income (Loss), Net of Tax		(1,203)	(37,943)
Foreign Currency Translation Adjustment [Member]
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax		(486)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		0
Other Comprehensive Income (Loss), before tax		(486)	(37,376)
Other Comprehensive Income (Loss), income tax		0	0
Other Comprehensive Income (Loss), Net of Tax		(486)	(37,376)
Pension and Other Postretirement Plans [Member]
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax		0
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax		(1,637)	891
Reclassification from AOCI, Current Period, Tax		443	(241)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		(1,194)	650
Other Comprehensive Income (Loss), before tax		(1,637)	891
Other Comprehensive Income (Loss), income tax		443	(241)
Other Comprehensive Income (Loss), Net of Tax		(1,194)	650
Net Prior Service (Credit) Cost [Member]
Other Comprehensive Income (Loss) [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[1]	792	671
Reclassification from AOCI, Current Period, Tax		(213)	(181)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		579	490
Net Actuarial Gain [Member]
Other Comprehensive Income (Loss) [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[1]	(2,429)	220
Reclassification from AOCI, Current Period, Tax		656	(60)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		(1,773)	160
Cash Flow Hedges [Member]
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax		323
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		154
Other Comprehensive Income (Loss), before tax		621	(1,578)
Other Comprehensive Income (Loss), income tax		(144)	361
Other Comprehensive Income (Loss), Net of Tax		$ 477	$ (1,217)

[1] These accumulated other comprehensive income components are included in the computation of net periodic pension and postretirement plan cost (see Note 12) and are included in non-operating pension and postretirement benefit income in the Company’s Condensed Consolidated Statements of Operations.