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Percentage of foreign revenue.

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The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

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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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Segment Information - Narrative (Details) $ in Thousands	3 Months Ended								12 Months Ended
Segment Information - Narrative (Details) $ in Thousands	Dec. 31, 2019 USD ($)	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) Segment Divisions	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| Segment									2
Number of internal divisions \| Divisions									2
Revenues	$ 3,112,800	$ 3,352,895	$ 2,839,199	$ 2,807,259	$ 3,112,218	$ 2,985,281	$ 2,656,348	$ 2,417,576	$ 12,112,153	$ 11,171,423	$ 9,466,478
Operating income (loss)									554,874	540,269	378,849
Property and equipment					1,276,032					1,276,032
Non-US
Segment Reporting Information [Line Items]
Revenues									1,920,000	2,600,000	$ 2,480,000
Property and equipment	$ 314,100				$ 304,000				314,100	304,000
Canada
Segment Reporting Information [Line Items]
Revenues									$ 1,436,720	$ 1,984,214
Percentage of foreign revenues									75.00%	76.00%	79.00%
Termination of the Peru Telecommunications Project
Segment Reporting Information [Line Items]
Charge to earnings related to legal proceedings									$ 79,200
Termination of the Peru Telecommunications Project \| Revenues
Segment Reporting Information [Line Items]
Charge to earnings related to legal proceedings									48,800
Termination of the Peru Telecommunications Project \| Cost of Services
Segment Reporting Information [Line Items]
Charge to earnings related to legal proceedings									30,400
Electric Power Infrastructure Services \| Operating Segments
Segment Reporting Information [Line Items]
Revenues									7,121,837	$ 6,415,562	$ 5,599,836
Operating income (loss)									591,177	628,286	518,130
Electric Power Infrastructure Services \| Operating Segments \| Latin America
Segment Reporting Information [Line Items]
Revenues									63,200	96,100	100,400
Operating income (loss)									$ (85,700)	$ (8,100)	$ 1,900