Segments and Geographic Information (Reconciliation of Segment EBIT to Net Income) (Details) $ in Thousands		12 Months Ended
		Dec. 31, 2016 USD ($) segment	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment		3
Net Sales:
Net sales		$ 793,420	$ 822,345	$ 852,492
Segment EBIT:
Segment EBIT		88,560	108,064	113,559
Reconciliation of Segment EBIT to Net Income:
Retained corporate costs		(27,265)	(34,645)	(30,558)
Loss on redemption of debt (note 6)		0	0	(47,191)
Pension settlement charges (note 9)		(168)	(21,693)	(774)
Furnace malfunction (note 18)		0	0	4,782
Environmental obligation (note 18)		0	(157)	(315)
Restructuring charges (note 7)		0	0	(985)
Product portfolio optimization (1)	[1]	(5,693)	0	0
Reorganization charges (2)	[2]	0	(4,316)	0
Derivatives (3)	[3]	1,860	218	(1,247)
Work stoppage (4)	[4]	(4,162)	0	0
Executive terminations		(4,460)	(870)	(875)
Interest expense		(20,888)	(18,484)	(22,866)
(Provision) benefit for income taxes		(17,711)	38,216	(8,567)
Net income		10,073	66,333	4,963
Depreciation & Amortization:
Depreciation and amortization		48,486	42,712	40,388
Capital Expenditures:
Capital Expenditures		34,604	48,136	54,393
Segment Assets:
Accounts Receivable, Net and Inventory, Net		255,122	272,406	260,934
U.S. & Canada
Net Sales:
Net sales		488,162	497,728	482,094
Segment EBIT:
Segment EBIT		77,916	80,406	72,546
Depreciation & Amortization:
Depreciation and amortization		12,748	12,214	10,319
Capital Expenditures:
Capital Expenditures		10,671	25,106	21,927
Segment Assets:
Accounts Receivable, Net and Inventory, Net		130,390	140,840	129,676
Latin America
Net Sales:
Net sales		151,406	167,069	190,079
Segment EBIT:
Segment EBIT		10,731	22,017	32,909
Depreciation & Amortization:
Depreciation and amortization		19,068	14,738	12,562
Capital Expenditures:
Capital Expenditures		11,032	11,944	22,517
Segment Assets:
Accounts Receivable, Net and Inventory, Net		63,838	68,599	66,726
EMEA
Net Sales:
Net sales		119,750	122,664	147,587
Segment EBIT:
Segment EBIT		(1,002)	1,251	5,726
Depreciation & Amortization:
Depreciation and amortization		9,377	8,510	10,061
Capital Expenditures:
Capital Expenditures		7,571	6,773	6,471
Segment Assets:
Accounts Receivable, Net and Inventory, Net		44,588	48,924	48,557
Other Segments
Net Sales:
Net sales		34,102	34,884	32,732
Segment EBIT:
Segment EBIT		915	4,390	2,378
Depreciation & Amortization:
Depreciation and amortization		5,588	5,855	6,179
Capital Expenditures:
Capital Expenditures		2,905	1,855	1,983
Segment Assets:
Accounts Receivable, Net and Inventory, Net		16,306	14,043	15,975
Corporate
Depreciation & Amortization:
Depreciation and amortization		1,705	1,395	1,267
Capital Expenditures:
Capital Expenditures		$ 2,425	$ 2,458	$ 1,495

[1] Product portfolio optimization relates to inventory reductions to simplify and improve our operations.

[2] Management reorganization to support our growth strategy.

[3] Derivatives relate to hedge ineffectiveness on our natural gas contracts and interest rate swap, as well as, mark-to-market adjustments on our natural gas contracts that have been de-designated and those for which we did not elect hedge accounting.

[4] Work stoppage relates to the lower production volume impact, shipping costs and other direct incremental expenses associated with the two-week Toledo, Ohio work stoppage in the fourth quarter of 2016.