Represents net estimated gross profit (loss) before tax.

No definition available.

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- Definition

Revenue From Contract With Customer, Number Of Contracts

+ References

No definition available.

+ Details

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- Definition

Represents the length of time the Company's contracts generally take to complete.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130556-203045

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- Definition

Amount of cost incurred on construction contract for unapproved change order, claim, or similar item subject to uncertainty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Revenue From Contracts With Customers - Narrative (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($) contract	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Disaggregation of Revenue [Line Items]
Remaining performance obligation	$ 808,740
Heavy Civil Construction
Disaggregation of Revenue [Line Items]
Number of contracts (more than) \| contract	150
Costs and Estimated Earnings in Excess of Billings
Disaggregation of Revenue [Line Items]
Contracts receivable unpaid project contract price	$ 9,300		$ 9,300
Operating income (Loss)
Disaggregation of Revenue [Line Items]
Estimated construction gain (loss) before tax	$ (200)	$ 1,300
Transferred over Time \| Product Concentration Risk \| Revenue from Contract with Customer
Disaggregation of Revenue [Line Items]
Concentration risk, percentage	81.00%	84.00%
Transferred at Point in Time \| Product Concentration Risk \| Revenue from Contract with Customer
Disaggregation of Revenue [Line Items]
Concentration risk, percentage	19.00%	16.00%
Minimum
Disaggregation of Revenue [Line Items]
Revenue recognition, contract term	12 months
Maximum
Disaggregation of Revenue [Line Items]
Revenue recognition, contract term	36 months