Accumulated Other Comprehensive Income (Loss) (Reclassifications out of AOCI) (Details 3) - USD ($) $ in Thousands		3 Months Ended						9 Months Ended
		Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Interest expense		$ 7,247			$ 6,776			$ 22,302	$ 22,587
Provision for Income Taxes		30,000			15,200			26,500	59,500
Net of Tax		(78,054)	$ (18,862)	$ 33,891	(42,965)	$ (57,195)	$ (81,702)	(63,025)	(181,862)
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Net of Tax		878			(1,066)			2,461	(3,574)
Foreign Currency Translation Adjustment [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, net of tax								0
Pension and Other Postretirement Plans [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, before tax		975			(1,443)			2,924	(4,744)
Provision for Income Tax		(263)			390			(789)	1,281
Reclassifications, net of tax		712			(1,053)			2,135	(3,463)
Net Prior Service (Credit) Cost [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, before tax	[1]	671			(932)			2,010	(3,210)
Provision for Income Tax		(180)			252			(542)	867
Reclassifications, net of tax		491			(680)			1,468	(2,343)
Net Actuarial Gain [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, before tax	[1]	304			(511)			914	(1,534)
Provision for Income Tax		(83)			138			(247)	414
Reclassifications, net of tax		221			(373)			667	(1,120)
Cash Flow Hedges [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, net of tax								326
Cash Flow Hedges [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Interest expense		166			(24)			313	(151)
Provision for Income Taxes		0			11			13	40
Net of Tax		$ 166			$ (13)			$ 326	$ (111)

[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.