Accounting Policies (Details) - USD ($)		3 Months Ended				9 Months Ended
	Mar. 31, 2014	Sep. 30, 2015	Sep. 30, 2014	Mar. 31, 2014	Sep. 30, 2013	Sep. 30, 2015	Sep. 30, 2014	Oct. 30, 2015	Dec. 31, 2014	Feb. 28, 2014	Dec. 31, 2013
Accounting Policies [Line Items]
Share Price		$ 16.48	$ 22.25			$ 16.48	$ 22.25
Tangible Asset Impairment Charges			$ 11,900,000
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest		$ 634,737,000	691,428,000			$ 634,737,000	$ 691,428,000		$ 645,085,000		$ 726,921,000
Foreign Currency Transaction Gain (Loss), Realized		139,000	(100,000)			(284,000)	(149,000)
Accumulated income (loss) related to currency translation adjustments		(44,500,000)	(13,900,000)			(44,500,000)	(13,900,000)
Accumulated income (loss) related to derivative transactions		(500,000)	(100,000)			(500,000)	(100,000)
Accumulated income (loss) related to pension activity		500,000	(200,000)			500,000	(200,000)
Proceeds from sale of interests in Bayou Coating, L.L.C.						0	9,065,000
Equity in earnings of affiliated companies		0	0			0	677,000
Proceeds from equity method investment						0	684,000
Loss on sale of interests in Bayou Coating, L.L.C.						0	472,000
Payments to purchase noncontrolling interest						0	617,000
Investment in affiliated companies		0				0			$ 0
Definite-lived intangible asset impairment		$ 0			$ 10,896,000	$ 0	$ 10,896,000
Bayou [Member]
Accounting Policies [Line Items]
Tangible Asset Impairment Charges			10,900,000
Definite-lived intangible asset impairment			10,900,000
Bayou [Member]
Accounting Policies [Line Items]
Tangible Asset Impairment Charges			400,000
Bayou Coating [Member]
Accounting Policies [Line Items]
Percent of book value	49.00%			49.00%							49.00%
Percent interest by noncontrolling owners	51.00%			51.00%
Proceeds from sale of interests in Bayou Coating, L.L.C.	$ 9,100,000
Equity in earnings of affiliated companies				$ 1,200,000
Proceeds from equity method investment				$ 700,000
Delta Double Jointing [Member]
Accounting Policies [Line Items]
Percent interest by noncontrolling owners										41.00%
Percent ownership interest by parent										59.00%
Payments to purchase noncontrolling interest	$ 600,000
FRANCE
Accounting Policies [Line Items]
Tangible Asset Impairment Charges			200,000
MALAYSIA
Accounting Policies [Line Items]
Tangible Asset Impairment Charges			300,000
INDIA
Accounting Policies [Line Items]
Tangible Asset Impairment Charges			$ 100,000
Maximum [Member]
Accounting Policies [Line Items]
Share Price		$ 19.77				$ 19.77
Minimum [Member]
Accounting Policies [Line Items]
Share Price		$ 16.03				$ 16.03
Subsequent Event [Member]
Accounting Policies [Line Items]
Share Price								$ 19.29