Accumulated Other Comprehensive Income (Loss) (Components of OCI) (Details 1) - USD ($) $ in Thousands		3 Months Ended				6 Months Ended
		Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before tax		$ (12,470)		$ (34,020)		$ (4,799)	$ (23,511)
Other Comprehensive Income (Loss), income tax		375		799		994	1,102
Other Comprehensive Income (Loss), Net of Tax		(12,095)	$ 8,290	(33,221)	$ 10,812	(3,805)	(22,409)
Foreign Currency Translation Adjustment [Member]
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax						(1,071)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax						0
Other Comprehensive Income (Loss), before tax		(11,104)		(31,167)		(1,071)	(19,603)
Other Comprehensive Income (Loss), income tax		0		0		0	0
Other Comprehensive Income (Loss), Net of Tax		(11,104)		(31,167)		(1,071)	(19,603)
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		(1,406)		(3,224)		(3,301)	(4,515)
Reclassification from AOCI, Current Period, Tax		380		869		891	1,217
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		(1,026)		(2,355)		(2,410)	(3,298)
Other Comprehensive Income (Loss), before tax		(1,406)		(3,224)		(3,301)	(4,515)
Other Comprehensive Income (Loss), income tax		380		869		891	1,217
Other Comprehensive Income (Loss), Net of Tax		(1,026)		(2,355)		(2,410)	(3,298)
Net Prior Service (Credit) Cost [Member]
Other Comprehensive Income (Loss) [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[1]	(931)		70		(2,278)	146
Reclassification from AOCI, Current Period, Tax		251		(19)		615	(40)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		(680)		51		(1,663)	106
Net Actuarial Gain [Member]
Other Comprehensive Income (Loss) [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	[1]	(475)		(3,294)		(1,023)	(4,661)
Reclassification from AOCI, Current Period, Tax		129		888		276	1,257
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax		(346)		(2,406)		(747)	(3,404)
Cash Flow Hedges [Member]
Other Comprehensive Income (Loss) [Line Items]
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax						(226)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax						(98)
Other Comprehensive Income (Loss), before tax		40		371		(427)	607
Other Comprehensive Income (Loss), income tax		(5)		(70)		103	(115)
Other Comprehensive Income (Loss), Net of Tax		$ 35		$ 301		$ (324)	$ 492

[1] These accumulated other comprehensive income components are components 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.