Organization And Description Of Business [Line Items]

No definition available.

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- Definition

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64827811&loc=d3e1361-107760

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 3B
-URI http://asc.fasb.org/extlink&oid=65878427&loc=SL51721525-107759

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5C
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721675-107760

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=65878427&loc=d3e957-107759

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

+ Details

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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- Definition

This element represents the cash inflow during the period from the sale of a component of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3179-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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Business and Organization - Additional Information (Detail) $ in Millions		3 Months Ended	12 Months Ended
	Aug. 04, 2015 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2016 Segment Acquisition	Dec. 31, 2015 Entity	Dec. 31, 2014 Entity
Organization And Description Of Business [Line Items]
Number of reportable segments \| Segment			2
Acquisitions 2014 [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions					9
Acquisitions 2014 [Member] \| Electric Power Infrastructure Services Business [Member] \| United States [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions					1
Acquisitions 2014 [Member] \| Electric Power Infrastructure Services Business [Member] \| Australia [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions					1
Acquisitions 2014 [Member] \| Electric Power Infrastructure Services Business [Member] \| Canada [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions					4
Acquisitions 2014 [Member] \| Oil and Gas Infrastructure Services Business [Member] \| United States [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions					1
Acquisitions 2014 [Member] \| Oil and Gas Infrastructure Services Business [Member] \| Canada [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions					2
Acquisitions 2015 [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions				11
Acquisitions 2015 [Member] \| Electric Power Infrastructure Services Business [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions				8
Acquisitions 2015 [Member] \| Electric Power Infrastructure Services Business [Member] \| United States [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions				4
Acquisitions 2015 [Member] \| Electric Power Infrastructure Services Business [Member] \| Australia [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions				1
Acquisitions 2015 [Member] \| Electric Power Infrastructure Services Business [Member] \| Canada [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions				3
Acquisitions 2015 [Member] \| Oil and Gas Infrastructure Services Business [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions				3
Acquisitions 2015 [Member] \| Oil and Gas Infrastructure Services Business [Member] \| United States [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions				1
Acquisitions 2015 [Member] \| Oil and Gas Infrastructure Services Business [Member] \| Australia [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions				1
Acquisitions 2015 [Member] \| Oil and Gas Infrastructure Services Business [Member] \| Canada [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions				1
Acquisitions 2016 [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions \| Acquisition			5
Acquisitions 2016 [Member] \| Electric Power Infrastructure Services Business [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions \| Acquisition			4
Acquisitions 2016 [Member] \| Electric Power Infrastructure Services Business [Member] \| United States [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions \| Acquisition			1
Acquisitions 2016 [Member] \| Electric Power Infrastructure Services Business [Member] \| Australia [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions \| Acquisition			1
Acquisitions 2016 [Member] \| Electric Power Infrastructure Services Business [Member] \| Canada [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions \| Acquisition			2
Acquisitions 2016 [Member] \| Oil and Gas Infrastructure Services Business [Member] \| United States [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions \| Acquisition			1
Fiber Optic Licensing Division [Member]
Organization And Description Of Business [Line Items]
Sales price of fiber optic licensing operations \| $	$ 1,000
Net cash proceeds from sale of fiber optic licensing operations \| $	$ 848
Gain on sale, Net of tax \| $		$ 171