Contract With Customer, Contract Value

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- Definition

Contract With Customer, Cumulative Catch-Up Adjustment To Gross Profit, Change In Estimate

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- Definition

Contract With Customer, Liability, Deferred Revenues, Current

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- Definition

Contract With Customer, Percentage Of Completion

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- Definition

Revenue From Contract With Customer, Percentage Of Revenue Recognized Over Time

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- Definition

Revenue Recognized, Related To Unapproved Change Orders And Claims

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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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- Definition

Amount of revenue recognized from performance obligation satisfied or partially satisfied in previous reporting periods. Includes, but is not limited to, change in transaction price.

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- Definition

Amount of the cumulative effect on retained earnings before related income tax effect.

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Amount of the related income tax effect of a cumulative effect on retained earnings.

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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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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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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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Summary of Significant Accounting Policies - Revenue Recognition (Details) - USD ($) $ in Thousands		3 Months Ended								12 Months Ended
	Jan. 01, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Reduction to retained earnings due to adoption of new guidance		$ (2,477,291)				$ (2,191,059)				$ (2,477,291)	$ (2,191,059)
Additional revenues that would have been recognized under previous guidance		3,112,218	$ 2,985,281	$ 2,656,348	$ 2,417,576	2,478,627	$ 2,609,307	$ 2,200,374	$ 2,178,170	11,171,423	9,466,478	$ 7,651,319
Remaining performance obligation		4,680,000								4,680,000
Revenues recognized related to change orders and claims		121,800				144,000				121,800	144,000
Change in contract estimates, favorable (unfavorable) impact on revenues										71,900
Revenue recognized related to amounts in contract liabilities outstanding at the beginning of period										$ 400,000
Percent of total revenues recognized associated with revenue recognition method										57.70%
Unearned revenues		$ 40,083				15,967				$ 40,083	15,967
EPC Electric Transmission Project
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Change in contract estimates, favorable (unfavorable) impact on operating results										(52,200)
$150 Million Lump-Sum Processing Facility Construction Project
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Change in contract estimates, favorable (unfavorable) impact on operating results										$ 34,200
Percentage of completion		88.00%								88.00%
Lump-sum amount		$ 150,000								$ 150,000
Electric Power Project
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Change in contract estimates, favorable (unfavorable) impact on operating results										$ 22,300
Percentage of completion		86.00%								86.00%
Lump-sum amount		$ 75,000								$ 75,000
$50 Million Lump Sum Natural Gas Pipeline Construction Project
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Change in contract estimates, favorable (unfavorable) impact on operating results										$ 17,300
Percentage of completion		99.00%								99.00%
Lump-sum amount		$ 50,000								$ 50,000
Accounts Payable and Accrued Expenses
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Unearned revenues		$ 40,100				$ 16,000				40,100	$ 16,000
Accounting Standards Update 2014-09 \| Adjustment Due to Adoption of New Guidance
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Reduction to retained earnings due to adoption of new guidance													$ 1,300
Reduction to retained earnings due to adoption of new guidance, gross adjustment	$ 1,800
Reduction to retained earnings due to adoption of new guidance, tax	$ 500
Additional revenues that would have been recognized under previous guidance										$ 2,000