Restructuring - Restructuring Reserve by Type of Cost (Details) - Restructuring Plan 2014 [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Restructuring Cost and Reserve [Line Items]
Other non-cash restructuring charges (reversals)		$ 39,953		$ 39,953
Cash restructuring charges		0		0
Pre-tax charges related to restructuring		39,953		39,953
Cost of revenues [Member]
Restructuring Cost and Reserve [Line Items]
Other non-cash restructuring charges (reversals)		14,940		14,940
Cash restructuring charges		0		0
Pre-tax charges related to restructuring		14,940		14,940
Infrastructure Solutions [Member]
Restructuring Cost and Reserve [Line Items]
Other non-cash restructuring charges (reversals)	$ 915		$ 4,991
Cash restructuring charges	583		5,739
Pre-tax charges related to restructuring	1,498		10,730	17,800
Infrastructure Solutions [Member] | Cost of revenues [Member]
Restructuring Cost and Reserve [Line Items]
Other non-cash restructuring charges (reversals)	1,678		1,546	3,600
Cash restructuring charges	(17)		1,097
Pre-tax charges related to restructuring	1,661		2,643
Infrastructure Solutions [Member] | Operating expenses [Member]
Restructuring Cost and Reserve [Line Items]
Other non-cash restructuring charges (reversals)	(829)	14,117	441	14,117
Cash restructuring charges	386	0	3,748	0
Pre-tax charges related to restructuring	(443)	14,117	4,189	14,117
Infrastructure Solutions [Member] | Restructuring charges [Member]
Restructuring Cost and Reserve [Line Items]
Other non-cash restructuring charges (reversals)	0		0
Cash restructuring charges	172		1,034
Pre-tax charges related to restructuring	172		1,034
Infrastructure Solutions [Member] | Other expense [Member]
Restructuring Cost and Reserve [Line Items]
Other non-cash restructuring charges (reversals)	66		3,004
Cash restructuring charges	42		(140)
Pre-tax charges related to restructuring	$ 108		$ 2,864
Corrosion Protection [Member]
Restructuring Cost and Reserve [Line Items]
Pre-tax charges related to restructuring				22,200
Corrosion Protection [Member] | Cost of revenues [Member]
Restructuring Cost and Reserve [Line Items]
Other non-cash restructuring charges (reversals)				11,300
Corrosion Protection [Member] | Restructuring charges [Member]
Restructuring Cost and Reserve [Line Items]
Other non-cash restructuring charges (reversals)		10,896		10,896
Cash restructuring charges		0		0
Pre-tax charges related to restructuring		$ 10,896		$ 10,896