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
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-Publisher FASB
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-Publisher FASB
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
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-URI http://asc.fasb.org/extlink&oid=51716988&loc=d3e957-107759

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Balance Type:	credit
Period Type:	duration

- 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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Balance Type:	debit
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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)
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-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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- Details

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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, 2015 Entity Segment	Dec. 31, 2014 Entity	Dec. 31, 2013 Entity
Organization And Description Of Business [Line Items]
Number of reportable segments \| Segment			2
Number of business acquisitions			11	9	6
Electric Power Infrastructure Services Business [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions			8
Electric Power Infrastructure Services Business [Member] \| Canada [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions			3	4
Electric Power Infrastructure Services Business [Member] \| Australia [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions			1	1
Electric Power Infrastructure Services Business [Member] \| United States [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions			4	1
Electric Power Infrastructure Services Business [Member] \| United States Canada And Australia [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions					3
Oil and Gas Infrastructure Services Business [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions			3
Oil and Gas Infrastructure Services Business [Member] \| Canada [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions			1	2
Oil and Gas Infrastructure Services Business [Member] \| Australia [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions			1
Oil and Gas Infrastructure Services Business [Member] \| United States [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions			1	1
Oil and Gas Infrastructure Services Business [Member] \| United States Canada And Australia [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions					3
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