Goodwill and Other Intangible Assets (Goodwill by Segment Rollforward) (Details) (USD $)	9 Months Ended
	Sep. 30, 2013
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 824,953,000
Additions from new business combinations, goodwill	61,500,000
Currency translation adjustments, goodwill	(1,700,000)
Goodwill, ending balance	891,266,000
Earn-out Arrangements [Member]
Goodwill [Roll Forward]
Accruals of acquisition-related contingent consideration	6,500,000	[1]
Reportable Segments [Member] | Communications [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	305,800,000
Additions from new business combinations, goodwill	10,000,000
Currency translation adjustments, goodwill	0
Goodwill, ending balance	322,300,000
Reportable Segments [Member] | Communications [Member] | Earn-out Arrangements [Member]
Goodwill [Roll Forward]
Accruals of acquisition-related contingent consideration	6,500,000	[1]
Reportable Segments [Member] | Oil and Gas [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	272,100,000
Additions from new business combinations, goodwill	32,300,000
Currency translation adjustments, goodwill	(1,700,000)
Goodwill, ending balance	302,700,000
Reportable Segments [Member] | Oil and Gas [Member] | Earn-out Arrangements [Member]
Goodwill [Roll Forward]
Accruals of acquisition-related contingent consideration	0	[1]
Reportable Segments [Member] | Electrical Transmission [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	129,500,000
Additions from new business combinations, goodwill	19,200,000
Currency translation adjustments, goodwill	0
Goodwill, ending balance	148,700,000
Reportable Segments [Member] | Electrical Transmission [Member] | Earn-out Arrangements [Member]
Goodwill [Roll Forward]
Accruals of acquisition-related contingent consideration	0	[1]
Reportable Segments [Member] | Power Generation and Industrial [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	117,600,000
Additions from new business combinations, goodwill	0
Currency translation adjustments, goodwill	0
Goodwill, ending balance	117,600,000
Reportable Segments [Member] | Power Generation and Industrial [Member] | Earn-out Arrangements [Member]
Goodwill [Roll Forward]
Accruals of acquisition-related contingent consideration	$ 0	[1]

[1] Represents contingent consideration for acquisitions prior to January 1, 2009, which is only accrued as earned, in accordance with U.S. GAAP.