Accumulated Other Comprehensive Income (Loss) (Components of OCI) (Details 1) - USD ($) $ in Thousands		3 Months Ended				6 Months Ended
		Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before tax		$ 1,048		$ 17,320		$ (454)	$ (20,743)
Other Comprehensive Income (Loss), income tax		32		(252)		331	(132)
Other Comprehensive Income (Loss), Net of Tax		1,080	$ (1,203)	17,068	$ (37,943)	(123)	(20,875)
Foreign Currency Translation Adjustment [Member]
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax						681
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax						0
Other Comprehensive Income (Loss), before tax		1,167		16,405		681	(20,971)
Other Comprehensive Income (Loss), income tax		0		0		0	0
Other Comprehensive Income (Loss), Net of Tax		1,167		16,405		681	(20,971)
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		(132)		1,058		(1,769)	1,949
Reclassification from AOCI, Current Period, Tax		35		(285)		478	(526)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		(97)		773		(1,291)	1,423
Other Comprehensive Income (Loss), before tax		(132)		1,058		(1,769)	1,949
Other Comprehensive Income (Loss), income tax		35		(285)		478	(526)
Other Comprehensive Income (Loss), Net of Tax		(97)		773		(1,291)	1,423
Net Prior Service (Credit) Cost [Member]
Other Comprehensive Income (Loss) [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[1]	792		668		1,584	1,339
Reclassification from AOCI, Current Period, Tax		(214)		(181)		(427)	(362)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		578		487		1,157	977
Net Actuarial Gain [Member]
Other Comprehensive Income (Loss) [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[1]	(924)		390		(3,353)	610
Reclassification from AOCI, Current Period, Tax		249		(104)		905	(164)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		(675)		286		(2,448)	446
Cash Flow Hedges [Member]
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax						180
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax						307
Other Comprehensive Income (Loss), before tax		13		(143)		634	(1,721)
Other Comprehensive Income (Loss), income tax		(3)		33		(147)	394
Other Comprehensive Income (Loss), Net of Tax		$ 10		$ (110)		$ 487	$ (1,327)

[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.