Restructuring - Restructuring Costs by Segment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	$ 1,535	$ 204	$ 8,332	$ 862
Restructuring Plan 2016
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	3,763		13,505
Restructuring Plan 2016 | Corporate, Non-Segment
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	200		1,200
Restructuring Plan 2016 | Severance and benefit related costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	1,152		6,793
Restructuring Plan 2016 | Lease termination costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring			969
Restructuring Plan 2016 | Relocation and other moving costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	383		503
Restructuring Plan 2016 | Other restructuring costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	2,228		5,240
Restructuring Plan 2016 | Infrastructure Solutions
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	1,219		3,372
Restructuring Plan 2016 | Infrastructure Solutions | Severance and benefit related costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	344		2,256
Restructuring Plan 2016 | Infrastructure Solutions | Lease termination costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring			0
Restructuring Plan 2016 | Infrastructure Solutions | Relocation and other moving costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	307		307
Restructuring Plan 2016 | Infrastructure Solutions | Other restructuring costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	568		809
Restructuring Plan 2016 | Corrosion Protection
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	957		3,694
Restructuring Plan 2016 | Corrosion Protection | Severance and benefit related costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	714		3,134
Restructuring Plan 2016 | Corrosion Protection | Lease termination costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring			0
Restructuring Plan 2016 | Corrosion Protection | Relocation and other moving costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	62		62
Restructuring Plan 2016 | Corrosion Protection | Other restructuring costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	181		498
Restructuring Plan 2016 | Energy Services
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	1,587		6,439	$ 6,400
Restructuring Plan 2016 | Energy Services | Severance and benefit related costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	94		1,403
Restructuring Plan 2016 | Energy Services | Lease termination costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring			969
Restructuring Plan 2016 | Energy Services | Relocation and other moving costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	14		134
Restructuring Plan 2016 | Energy Services | Other restructuring costs
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring	$ 1,479		$ 3,933