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
-Topic 910
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6471471&loc=d3e48698-109348

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Revenue From Contracts With Customers - Narrative (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019 USD ($) contract	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($) contract	Jun. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Disaggregation of Revenue [Line Items]
Remaining performance obligation	$ 909.0		$ 909.0
Heavy Civil Construction
Disaggregation of Revenue [Line Items]
Number of contracts (more than) \| contract	150		150
Costs and Estimated Earnings in Excess of Billings
Disaggregation of Revenue [Line Items]
Contracts receivable unpaid project contract price	$ 15.7		$ 15.7		$ 9.3
Operating income (Loss)
Disaggregation of Revenue [Line Items]
Estimated construction gain (loss) before tax	$ 3.5	$ 0.3	$ 3.3	$ 1.7
Transferred over Time \| Product Concentration Risk \| Revenue from Contract with Customer
Disaggregation of Revenue [Line Items]
Concentration risk, percentage	86.00%	83.00%	84.00%	84.00%
Transferred at Point in Time \| Product Concentration Risk \| Revenue from Contract with Customer
Disaggregation of Revenue [Line Items]
Concentration risk, percentage	14.00%	17.00%	16.00%	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