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Percentage of foreign revenue.

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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.

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

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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.

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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.

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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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Segment Information - Narrative (Details) $ in Thousands	3 Months Ended		6 Months Ended
Segment Information - Narrative (Details) $ in Thousands	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) division Segment	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| Segment			2
Number of internal divisions \| division			2
Operating income (loss)	$ 161,651	$ 112,916	$ 275,380	$ 193,653
Revenues	2,999,816	2,506,231	5,703,397	5,270,326
Canada
Segment Reporting Information [Line Items]
Revenues	$ 327,159	$ 212,820	$ 741,005	$ 597,045
Percentage of foreign revenues	76.00%	71.00%	80.00%	75.00%
Foreign Countries
Segment Reporting Information [Line Items]
Revenues	$ 429,000	$ 298,400	$ 926,500	$ 794,400
Property and equipment	331,600		331,600		$ 336,400
Electric Power Infrastructure Solutions \| Operating Segments
Segment Reporting Information [Line Items]
Operating income (loss)	236,899	183,896	435,934	312,654
Revenues	$ 2,147,775	1,792,918	$ 4,207,895	3,559,945
Electric Power Infrastructure Solutions \| Operating Segments \| Latin America
Segment Reporting Information [Line Items]
Operating income (loss)		$ (15,200)		$ (31,500)