Fair Value Measurement, Assumptions Used to Calculate Reporting Unit Fair Value, Revenue Growth Rate, Period Evaluated

No definition available.

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- Definition

Goodwill Impairment, Segment Value

+ References

No definition available.

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- Definition

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

+ Details

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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.

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- Definition

Percentage of fair value of reporting unit in excess of carrying amount.

+ References

No definition available.

+ Details

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Summary of Significant Accounting Policies - Goodwill (Details) - USD ($) $ in Thousands		12 Months Ended
	Oct. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Goodwill		$ 66,351	$ 65,982	$ 33,798
Revenue growth rate implied in reporting units valuations, number of years projected		5 years
Heavy Civil Marine Construction Segment
Goodwill [Line Items]
Goodwill		$ 33,800
Discount rate	25.00%
Percentage of fair value in excess of carrying amt	33.30%
Commercial Concrete Segment
Goodwill [Line Items]
Goodwill		$ 32,600
Discount rate	20.00%
Percentage of fair value in excess of carrying amt	4.20%
Estimate of Fair Value Measurement \| Heavy Civil Marine Construction Segment
Goodwill [Line Items]
Goodwill impairment, segment value	$ 345,000
Estimate of Fair Value Measurement \| Commercial Concrete Segment
Goodwill [Line Items]
Goodwill impairment, segment value	126,000
Reported Value Measurement \| Heavy Civil Marine Construction Segment
Goodwill [Line Items]
Goodwill impairment, segment value	230,300
Reported Value Measurement \| Commercial Concrete Segment
Goodwill [Line Items]
Goodwill impairment, segment value	$ 120,700