Segment Information - Narrative (Details) $ in Thousands	3 Months Ended
Mar. 31, 2020 USD ($) Segment division	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| Segment	2
Number of internal divisions \| division	2
Revenues	$ 2,764,095	$ 2,807,259
Operating income (loss)	80,737	119,487
Canada
Segment Reporting Information [Line Items]
Revenues	$ 384,225	$ 485,430
Percentage of foreign revenues	77.00%	80.00%
Foreign Countries
Segment Reporting Information [Line Items]
Revenues	$ 496,000	$ 606,600
Property and equipment	291,400		$ 314,100
Electric Power Infrastructure Services \| Operating Segments
Segment Reporting Information [Line Items]
Revenues	1,767,027	1,664,023
Operating income (loss)	128,758	161,617
Electric Power Infrastructure Services \| Operating Segments \| Latin America
Segment Reporting Information [Line Items]
Revenues	4,700	27,800
Operating income (loss)	$ (16,300)	$ (600)

Number of internal divisions.

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- Definition

Percentage of foreign revenue.

+ References

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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

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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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.

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