Accumulated Other Comprehensive Loss (Components of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance				$ (462,243)
Before reclassifications to income and retained earnings				(121,159)
Reclassifications to income				8,279
Net other comprehensive income		$ (30,386)	$ 73,087	(112,880)	$ 98,620
Ending Balance		(575,123)		(575,123)
Reclassifications before taxes, included in net periodic benefit expense				8,851
Reclassifications, income tax expense				1,743
Reclassifications income tax, included in interest expense				311
Foreign Currency Translation Gains (Losses) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance				(274,830)
Before reclassifications to income and retained earnings				(87,185)
Net other comprehensive income				(87,185)
Ending Balance		(362,015)		(362,015)
Retirement and Postretirement Benefit Plan Adjustments [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance				(178,987)
Before reclassifications to income and retained earnings				(32,159)
Reclassifications to income	[1]			7,108
Net other comprehensive income				(25,051)
Ending Balance		(204,038)		(204,038)
Deferred Loss On Interest Rate Derivative Hedges [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance				(8,426)
Before reclassifications to income and retained earnings				(1,815)
Reclassifications to income	[2]			1,171
Net other comprehensive income				(644)
Ending Balance		$ (9,070)		$ (9,070)

[1] Reclassifications before taxes of $8,851 are included in the computation of net periodic benefit expense for the six-month period ended June 30, 2018. See Note H for additional information. Related income taxes of $1,743 are included in Income tax expense (benefit) for the six-month period ended June 30, 2018.

[2] Reclassifications before taxes of $1,482 are included in Interest expense, net, for the six-month period ended June 30, 2018. Related income taxes of $311 are included in Income tax expense (benefit) for the six-month period ended June 30, 2018. See Note L for additional information.