Segment Reporting - Financial Information by Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Segment Reporting Information [Line Items]
Revenues	$ 339,679	$ 341,872	$ 999,570	$ 1,021,520
Gross profit	72,673	73,442	205,230	220,622
Operating income (loss)	13,009	(75,271)	30,649	(39,564)
Interest expense	(3,870)	(3,962)	(13,236)	(12,014)
Interest income	130	33	239	117
Other	(9,281)	(798)	(10,049)	(1,593)
Total other expense	(13,021)	(4,727)	(23,046)	(13,490)
Income (loss) before taxes on income	(12)	(79,998)	7,603	(53,054)
Restructuring and related charges	1,219	5,439	4,548	5,439
Goodwill impairment	1,389	45,390	1,389	45,390
Definite-lived intangible asset impairment	870	41,032	870	41,032
Restructuring 2017
Segment Reporting Information [Line Items]
Restructuring and related charges	200		200
Infrastructure Solutions
Segment Reporting Information [Line Items]
Revenues	155,681	174,161	450,840	451,340
Gross profit	38,135	41,189	100,793	106,803
Operating income (loss)	10,398	(74,025)	19,563	(60,224)
Goodwill impairment		45,400	1,389	45,400
Definite-lived intangible asset impairment		41,000		41,000
Infrastructure Solutions \| Restructuring 2017
Segment Reporting Information [Line Items]
Restructuring and related charges	6,000	4,500	12,100	4,700
Corrosion Protection
Segment Reporting Information [Line Items]
Revenues	105,624	102,276	300,118	353,381
Gross profit	26,411	23,063	74,524	86,663
Operating income (loss)	2,463	(2,703)	6,184	15,803
Goodwill impairment			0
Corrosion Protection \| Restructuring 2017
Segment Reporting Information [Line Items]
Restructuring and related charges	1,200	2,200	3,200	2,200
Energy Services
Segment Reporting Information [Line Items]
Revenues	78,374	65,435	248,612	216,799
Gross profit	8,127	9,190	29,913	27,156
Operating income (loss)	148	1,457	4,902	4,857
Goodwill impairment			0
Australia and Denmark \| Infrastructure Solutions
Segment Reporting Information [Line Items]
Restructuring and related charges	200		500
Bayou
Segment Reporting Information [Line Items]
Gain (loss) on disposition of business	(8,700)		8,700
Bayou \| Corrosion Protection
Segment Reporting Information [Line Items]
Restructuring costs	$ 4,600	1,900		1,900
Environmental Techniques \| Infrastructure Solutions
Segment Reporting Information [Line Items]
Restructuring and related charges		$ 100		$ 700
Hebna \| Bayou \| Corrosion Protection
Segment Reporting Information [Line Items]
Restructuring and related charges			$ 5,500

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