Goodwill and Intangible Assets Goodwill (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Oct. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Goodwill	$ 66,351		$ 65,982	$ 33,798
Heavy Civil Marine Construction Segment
Goodwill [Line Items]
Goodwill	33,800
Commercial Concrete Segment
Goodwill [Line Items]
Goodwill	$ 32,600
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