Acquisitions - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
Mar. 31, 2014 Entity	Dec. 31, 2013 Entity
Business Acquisition [Line Items]
Number of business acquisitions	5	6
Cash paid for acquisitions	$ 79,900,000	$ 341,100,000
Number of shares granted for acquired company	393,052	3,547,482
Common stock value	36,604,000	88,895,000
Fair value of accounts receivable acquired	31,100,000	83,900,000
Goodwill acquired	54,645,000
Revenues contributed by acquisitions	37,000,000
Acquisition costs	4,200,000
Income (loss) before income taxes contributed by acquisitions	(100,000)
Electric Power Infrastructure Services Business [Member] \| Canada [Member]
Business Acquisition [Line Items]
Number of business acquisitions	4
Oil and Gas Infrastructure Services Business [Member] \| United States [Member]
Business Acquisition [Line Items]
Number of business acquisitions	1
Acquisitions [Member]
Business Acquisition [Line Items]
Goodwill expected to be deductible for income tax	7,600,000	213,600,000
Electric Power Division [Member]
Business Acquisition [Line Items]
Goodwill acquired	47,089,000
Electric Power Division [Member] \| Acquisitions [Member]
Business Acquisition [Line Items]
Goodwill acquired	47,000,000	112,500,000
Oil and Gas Infrastructure Division [Member]
Business Acquisition [Line Items]
Goodwill acquired	7,556,000
Oil and Gas Infrastructure Division [Member] \| Acquisitions [Member]
Business Acquisition [Line Items]
Goodwill acquired	$ 7,600,000	$ 143,300,000
Exchangeable Shares [Member] \| Canadian Subsidiaries [Member]
Business Acquisition [Line Items]
Number of shares granted for acquired company	899,858
Series G Preferred Stock [Member]
Business Acquisition [Line Items]
Number of shares granted for acquired company	1

Aggregate business acquisition consideration of acquired entity cash paid and liabilities incurred during period.

No definition available.

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- Definition

Income (loss) before income taxes contributed by acquisitions.

+ References

No definition available.

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- Definition

Revenues contributed by acquisitions.

+ References

No definition available.

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- Definition

The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-10.(c)(7)(ii))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 10

-Paragraph c

-Subparagraph 3(ii)(A)

-Article 4

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)(4)

-URI http://asc.fasb.org/extlink&oid=7488404&loc=d3e6927-128479

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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

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7488404&loc=d3e6927-128479

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)(1)

-URI http://asc.fasb.org/extlink&oid=6910749&loc=d3e4845-128472

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- Definition

Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6578-128477

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 30

-Section 30

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=6911251&loc=d3e6613-128477

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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

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

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- Definition

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

+ References

No definition available.

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