Accumulated Other Comprehensive Income (Loss) (Schedule of AOCI) (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Change in Accumulated Other Comprehensive Loss [Roll Forward]
Beginning balance		$ (115,148)	$ (117,580)	$ (125,197)	$ (120,232)
Other comprehensive income (loss)		3,570	378	14,244	(1,543)
Currency impact		110	(31)	(628)	481
Amounts reclassified from accumulated other comprehensive income (loss):
Amortization of actuarial loss (1)	[1]	1,386	1,491	4,138	4,050
Amortization of prior service cost (credit) (1)	[1]	(45)	47	(127)	142
Cost of sales		76	41	(81)	1,096
Interest expense		358	767	1,415	1,778
Current-period other comprehensive income (loss)		5,455	2,693	18,961	6,004
Tax effect		(786)	(644)	(4,243)	(1,303)
Ending balance		(110,479)	(115,531)	(110,479)	(115,531)
Foreign Currency Translation
Change in Accumulated Other Comprehensive Loss [Roll Forward]
Beginning balance		(20,831)	(22,587)	(27,828)	(22,913)
Other comprehensive income (loss)		3,477	407	10,474	459
Amounts reclassified from accumulated other comprehensive income (loss):
Current-period other comprehensive income (loss)		3,477	407	10,474	459
Tax effect		(827)	78	(827)	352
Ending balance		(18,181)	(22,102)	(18,181)	(22,102)
Derivative Instruments
Change in Accumulated Other Comprehensive Loss [Roll Forward]
Beginning balance		(913)	(3,561)	(515)	(1,860)
Other comprehensive income (loss)		93	(29)	(1,031)	(4,757)
Amounts reclassified from accumulated other comprehensive income (loss):
Cost of sales		76	41	(81)	1,096
Interest expense		358	767	1,415	1,778
Current-period other comprehensive income (loss)		527	779	303	(1,883)
Tax effect		70	(278)	(104)	683
Ending balance		(316)	(3,060)	(316)	(3,060)
Pension and Other Postretirement Benefits
Change in Accumulated Other Comprehensive Loss [Roll Forward]
Beginning balance		(93,404)	(91,432)	(96,854)	(95,459)
Other comprehensive income (loss)		0	0	4,801	2,755
Currency impact		110	(31)	(628)	481
Amounts reclassified from accumulated other comprehensive income (loss):
Amortization of actuarial loss (1)	[1]	1,386	1,491	4,138	4,050
Amortization of prior service cost (credit) (1)	[1]	(45)	47	(127)	142
Current-period other comprehensive income (loss)		1,451	1,507	8,184	7,428
Tax effect		(29)	(444)	(3,312)	(2,338)
Ending balance		$ (91,982)	$ (90,369)	$ (91,982)	$ (90,369)

[1] These accumulated other comprehensive income components are included in the computation of net periodic benefit cost within the cost of sales and selling, general and administrative expenses on the Condensed Consolidated Statements of Operations.