Restructuring - 2016 Restructuring (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, 2016 USD ($)	Dec. 31, 2015 USD ($) employee	Dec. 31, 2014 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring charges					$ 9,168	$ 968	$ 687
Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Estimated effect on future earnings					17,400
Total headcount reduction | employee						964
Number of positions eliminated (percent)						15.50%
Restructuring charges	$ 1,300	$ 1,300	$ 3,800	$ 9,700	16,100
Restructuring charges net of tax					10,300
Non-Cash Restructuring Charges					765
Cash Restructuring Charges					15,335
Restructuring charges, incurred					16,100
Cash					14,435
Utilized non-cash					765
Restructuring Reserve	900				900
Restructuring Plan 2016 | Cost of revenues
Restructuring Cost and Reserve [Line Items]
Non-Cash Restructuring Charges					0
Cash Restructuring Charges					278
Restructuring charges, incurred					278
Restructuring Plan 2016 | Operating expenses
Restructuring Cost and Reserve [Line Items]
Non-Cash Restructuring Charges					516
Cash Restructuring Charges					5,962
Restructuring charges, incurred					6,478
Restructuring Plan 2016 | Restructuring charges
Restructuring Cost and Reserve [Line Items]
Non-Cash Restructuring Charges					0
Cash Restructuring Charges					9,095
Restructuring charges, incurred					9,095
Restructuring Plan 2016 | Other expense
Restructuring Cost and Reserve [Line Items]
Non-Cash Restructuring Charges					249
Cash Restructuring Charges					0
Restructuring charges, incurred					249
Severance and benefit related costs | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					7,396
Cash					6,751
Utilized non-cash					0
Restructuring Reserve	645				645
Lease termination costs | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					1,137
Cash					1,012
Utilized non-cash					0
Restructuring Reserve	125				125
Relocation and other moving costs | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					562
Cash					552
Utilized non-cash					0
Restructuring Reserve	10				10
Other restructuring | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					7,005
Cash					6,120
Utilized non-cash					765
Restructuring Reserve	$ 120				120
Employee severance and lease termination | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					9,100
Infrastructure Solutions
Restructuring Cost and Reserve [Line Items]
Utilized non-cash							$ 21,700
Infrastructure Solutions | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Estimated effect on future earnings					1,200
Restructuring charges					3,364
Infrastructure Solutions | Restructuring Plan 2016 | Operating expenses
Restructuring Cost and Reserve [Line Items]
Restructuring charges, incurred					600
Infrastructure Solutions | Restructuring Plan 2016 | Restructuring charges
Restructuring Cost and Reserve [Line Items]
Restructuring charges, incurred					2,600
Infrastructure Solutions | Severance and benefit related costs | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					2,249
Infrastructure Solutions | Lease termination costs | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					0
Infrastructure Solutions | Relocation and other moving costs | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					307
Infrastructure Solutions | Other restructuring | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					808
Corrosion Protection | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Estimated effect on future earnings					6,600
Restructuring charges					4,565
Corrosion Protection | Restructuring Plan 2016 | Operating expenses
Restructuring Cost and Reserve [Line Items]
Restructuring charges, incurred					500
Corrosion Protection | Restructuring Plan 2016 | Restructuring charges
Restructuring Cost and Reserve [Line Items]
Restructuring charges, incurred					3,800
Corrosion Protection | Severance and benefit related costs | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					3,588
Corrosion Protection | Lease termination costs | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					154
Corrosion Protection | Relocation and other moving costs | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					62
Corrosion Protection | Other restructuring | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					761
Energy Services | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Estimated effect on future earnings					5,600
Restructuring charges					8,171
Energy Services | Restructuring Plan 2016 | Operating expenses
Restructuring Cost and Reserve [Line Items]
Restructuring charges, incurred					5,400
Energy Services | Restructuring Plan 2016 | Restructuring charges
Restructuring Cost and Reserve [Line Items]
Restructuring charges, incurred					2,700
Energy Services | Severance and benefit related costs | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					1,559
Energy Services | Lease termination costs | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					983
Energy Services | Relocation and other moving costs | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					193
Energy Services | Other restructuring | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges					5,436
Corporate, Non-Segment | Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Estimated effect on future earnings					4,000
Restructuring charges					$ 1,400