Segment and Geographic Information - Financial Information by Segment (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) lawsuit	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Segment Reporting Information [Line Items]
Revenues	$ 321,802	$ 308,524	$ 297,686	$ 293,908	$ 330,713	$ 356,595	$ 337,096	$ 309,166	$ 1,221,920	$ 1,333,570	$ 1,331,421
Operating income (loss)	26,315	20,505	8,145	(4,139)	(28,640)	24,938	14,523	9,125	50,826	19,946	(19,812)
Interest expense									(15,029)	(16,044)	(12,943)
Interest income									166	218	633
Other									(694)	(2,905)	(3,853)
Total other expense									(15,557)	(18,731)	(16,163)
Income (loss) before taxes on income									35,269	1,215	(35,975)
Total assets	1,193,582				1,254,013				1,193,582	1,254,013	1,291,133
Capital expenditures									38,760	29,454	32,899
Depreciation and amortization									46,719	43,791	44,312
Restructuring charges, net									15,900
Goodwill impairment					43,500				0	43,484	51,512
Definite-lived intangible asset impairment									0	0	12,116
Restructuring charges									9,168	968	687
Acquisition-related expenses									2,696	1,912	1,375
Gain on litigation settlement									$ 6,625	0	0
Number of lawsuits settled | lawsuit									2
Infrastructure Solutions
Segment Reporting Information [Line Items]
Revenues									$ 571,551	556,234	567,205
Operating income (loss)									53,503	46,867	(6,194)
Goodwill impairment											16,100
Definite-lived intangible asset impairment											1,200
Acquisition-related expenses									2,700	1,100
Gain on litigation settlement									6,600
Inventory step up expense									3,600
Corrosion Protection
Segment Reporting Information [Line Items]
Revenues									401,469	437,921	458,409
Operating income (loss)									1,809	(1,771)	(31,010)
Goodwill impairment										10,000	35,400
Definite-lived intangible asset impairment											10,900
Acquisition-related expenses										500	700
Energy Services
Segment Reporting Information [Line Items]
Revenues									248,900	339,415	305,807
Operating income (loss)									(4,486)	(25,150)	17,392
Goodwill impairment										33,500
Acquisition-related expenses										300	700
Proceeds from settlement of escrow claims											4,500
Operating Segments | Infrastructure Solutions
Segment Reporting Information [Line Items]
Total assets	584,425				508,817				584,425	508,817	485,785
Capital expenditures									19,834	7,657	13,096
Depreciation and amortization									17,547	14,836	15,726
Operating Segments | Corrosion Protection
Segment Reporting Information [Line Items]
Total assets	424,007				489,519				424,007	489,519	506,659
Capital expenditures									14,393	17,226	12,107
Depreciation and amortization									18,792	18,834	19,259
Operating Segments | Energy Services
Segment Reporting Information [Line Items]
Total assets	147,171				183,763				147,171	183,763	197,858
Capital expenditures									2,514	2,202	3,720
Depreciation and amortization									7,067	7,641	7,004
Corporate, Non-Segment
Segment Reporting Information [Line Items]
Total assets	37,979				50,854				37,979	50,854	100,831
Capital expenditures									2,019	2,369	3,976
Depreciation and amortization									3,313	2,480	2,323
Reconciling Items | Held-for-sale Assets
Segment Reporting Information [Line Items]
Total assets	0				21,060				0	21,060	0
Restructuring Plan 2016
Segment Reporting Information [Line Items]
Restructuring charges	1,300	1,300	3,800	9,700					16,100
Restructuring Plan 2016 | Infrastructure Solutions
Segment Reporting Information [Line Items]
Restructuring charges, net									3,100
Restructuring charges									3,364
Restructuring Plan 2016 | Corrosion Protection
Segment Reporting Information [Line Items]
Restructuring charges									4,565
Restructuring Plan 2016 | Energy Services
Segment Reporting Information [Line Items]
Restructuring charges									8,171
Restructuring Plan 2016 | Corporate, Non-Segment
Segment Reporting Information [Line Items]
Restructuring charges									1,400
Restructuring Plan 2014
Segment Reporting Information [Line Items]
Restructuring charges	$ 300	$ (400)	$ 100	$ (200)	$ 300	$ 1,500	$ 5,700	$ 3,500		8,100	47,800
Restructuring Plan 2014 | Infrastructure Solutions
Segment Reporting Information [Line Items]
Restructuring charges									$ (200)	$ 8,100	25,600
Restructuring Plan 2014 | Corrosion Protection
Segment Reporting Information [Line Items]
Restructuring charges											$ 11,300