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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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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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.

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- Definition

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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (b)

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-Glossary Investing Activities

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Business and Organization - Additional Information (Detail) $ in Millions		3 Months Ended			9 Months Ended	12 Months Ended
	Aug. 04, 2015 USD ($)	Sep. 30, 2015 USD ($) Entity	Jun. 30, 2015 Entity	Mar. 31, 2015 Entity	Sep. 30, 2015 Entity Segment	Dec. 31, 2014 Entity
Organization And Description Of Business [Line Items]
Number of reportable segments \| Segment					2
Number of business acquisitions		4	3	3	10	9
Electric Power Infrastructure Services Business [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions					7
Electric Power Infrastructure Services Business [Member] \| Canada [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions			1	1	2	4
Electric Power Infrastructure Services Business [Member] \| Australia [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions		1			1	1
Electric Power Infrastructure Services Business [Member] \| United States [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions		2	2		4	1
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	1	2
Oil and Gas Infrastructure Services Business [Member] \| Australia [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions				1	1
Oil and Gas Infrastructure Services Business [Member] \| United States [Member]
Organization And Description Of Business [Line Items]
Number of business acquisitions		1			1	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