Accounting Policies (Details) - USD ($)		3 Months Ended			6 Months Ended
	Mar. 31, 2014	Jun. 30, 2015	Jun. 30, 2014	Mar. 31, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014	Feb. 28, 2014	Dec. 31, 2013
Accounting Policies [Line Items]
Accumulated income (loss) related to currency translation adjustments		$ (41,900,000)	$ 2,500,000		$ (41,900,000)	$ 2,500,000
Accumulated income (loss) related to derivative transactions		(100,000)	(800,000)		(100,000)	(800,000)
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
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