Segments (Details) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) segment	Jun. 30, 2015 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment				3
Net Sales:
Net sales		$ 207,902	$ 214,051	$ 390,709	$ 401,416
Segment EBIT:
Segment EBIT		33,489	33,180	50,614	52,232
Reconciliation of Segment EBIT to Net Income:
Retained corporate costs		(7,050)	(9,162)	(13,774)	(18,657)
Pension settlement		(212)	0	(212)	0
Environmental obligation (note 13)		0	(223)	0	(223)
Reorganization charges (1)	[1]	0	(3,015)	0	(3,015)
Derivatives (2)	[2]	769	566	1,139	167
Product portfolio optimization (3)	[3]	(6,784)	0	(6,784)	0
Executive terminations		328	0	(4,619)	(235)
Interest expense		(5,154)	(4,538)	(10,398)	(9,061)
Income taxes		(6,691)	(2,414)	(6,553)	(3,702)
Net income		8,695	14,394	9,413	17,506
Depreciation & Amortization:
Depreciation and amortization		13,354	10,469	25,435	20,653
Capital Expenditures:
Capital Expenditures		5,656	16,577	15,511	33,236
United States & Canada
Net Sales:
Net sales		126,167	127,435	239,268	237,354
Segment EBIT:
Segment EBIT		24,927	25,315	38,239	36,175
Depreciation & Amortization:
Depreciation and amortization		3,379	2,987	6,835	5,779
Capital Expenditures:
Capital Expenditures		2,154	9,931	5,993	20,768
Latin America
Net Sales:
Net sales		40,619	44,614	74,839	84,466
Segment EBIT:
Segment EBIT		7,800	5,003	12,140	12,091
Depreciation & Amortization:
Depreciation and amortization		4,516	3,430	9,058	6,715
Capital Expenditures:
Capital Expenditures		1,380	4,329	3,676	8,010
EMEA
Net Sales:
Net sales		31,268	32,126	57,896	60,635
Segment EBIT:
Segment EBIT		(97)	1,786	(1,042)	1,020
Depreciation & Amortization:
Depreciation and amortization		3,617	2,137	5,775	4,314
Capital Expenditures:
Capital Expenditures		889	1,338	3,107	2,775
Other Segments
Net Sales:
Net sales		9,848	9,876	18,706	18,961
Segment EBIT:
Segment EBIT		859	1,076	1,277	2,946
Depreciation & Amortization:
Depreciation and amortization		1,409	1,481	2,837	2,972
Capital Expenditures:
Capital Expenditures		895	357	1,590	540
Corporate
Depreciation & Amortization:
Depreciation and amortization		433	434	930	873
Capital Expenditures:
Capital Expenditures		$ 338	$ 622	$ 1,145	$ 1,143

[1] Management reorganization to support our growth strategy.

[2] Derivatives relate to hedge ineffectiveness on our natural gas contracts, 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.

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