Accumulated Other Comprehensive Income (Loss) (Reclassifications out of AOCI) (Details 3) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Interest expense		$ 8,448	$ 7,678
Provision for (Benefit from) Income Taxes		41,400	(45,400)
Net of Tax		(112,635)	33,891
Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Net of Tax		(1,040)	686
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		(1,637)	891
Provision for (Benefit from) Income Tax		443	(241)
Reclassifications, net of tax		(1,194)	650
Net Prior Service (Credit) Cost [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, before tax	[1]	792	671
Provision for (Benefit from) Income Tax		(213)	(181)
Reclassifications, net of tax		579	490
Net Actuarial Gain [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, before tax	[1]	(2,429)	220
Provision for (Benefit from) Income Tax		656	(60)
Reclassifications, net of tax		(1,773)	160
Cash Flow Hedges [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Reclassifications, net of tax		154
Cash Flow Hedges [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Interest expense		154	29
Provision for (Benefit from) Income Taxes		0	7
Net of Tax		$ 154	$ 36

[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.