Amount of tangible assets acquired less liabilities assumed at the acquisition date.

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
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-Subparagraph (d)
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- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the fair value of the receivables acquired, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 20
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-Paragraph 1
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- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Acquisitions (2016 and 2015 Acquisitions) - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended			12 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2015	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015	Dec. 31, 2015
Business Acquisition [Line Items]
Goodwill acquired				$ 26,116			$ 51,641
Other intangible assets, acquired	$ 8,327			8,327	$ 24,987		24,987
Fair value of accounts receivable acquired	10,200			10,200	20,600		20,600
Income (loss) from continuing operations before income taxes	31,424		$ 67,047	65,726		$ 150,038
Electric Power Division [Member]
Business Acquisition [Line Items]
Goodwill acquired				5,829
Oil and Gas Infrastructure Division [Member]
Business Acquisition [Line Items]
Goodwill acquired				20,287
Acquisitions 2016 [Member]
Business Acquisition [Line Items]
Net tangible assets acquired		$ 23,200
Goodwill acquired		26,100
Other intangible assets, acquired		$ 8,300
Goodwill expected to be deductible for income tax	400			400
Revenues	18,900			24,500
Income (loss) from continuing operations before income taxes	$ 1,500			(1,000)
Acquisitions 2016 [Member] \| Electric Power Division [Member]
Business Acquisition [Line Items]
Goodwill acquired				5,800
Acquisitions 2016 [Member] \| Oil and Gas Infrastructure Division [Member]
Business Acquisition [Line Items]
Goodwill acquired				$ 20,300
Acquisitions 2015 [Member]
Business Acquisition [Line Items]
Net tangible assets acquired					19,400
Goodwill acquired					26,400
Other intangible assets, acquired					10,200		10,200
Goodwill expected to be deductible for income tax					$ 33,900		33,900
Acquisitions 2015 [Member] \| Electric Power Division [Member]
Business Acquisition [Line Items]
Goodwill acquired							31,200
Acquisitions 2015 [Member] \| Oil and Gas Infrastructure Division [Member]
Business Acquisition [Line Items]
Goodwill acquired							$ 20,400