Segment Reporting - Summary (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Contract revenues	$ 137,061	$ 106,976	$ 304,607	$ 278,485
Operating (loss) income	(6,218)	$ 5,047	(9,223)	2,472
Depreciation and amortization expense			(18,831)	$ (17,631)
Total Assets	504,399		504,399		$ 352,300
Property and equipment, net	163,921		163,921		$ 161,773
Operating Segments | Heavy Civil Marine Construction
Segment Reporting Information [Line Items]
Contract revenues	90,068		257,614
Operating (loss) income	(8,584)		(11,589)
Depreciation and amortization expense	(5,585)		(16,239)
Total Assets	348,074		348,074
Property and equipment, net	149,162		149,162
Operating Segments | Commercial Concrete Construction
Segment Reporting Information [Line Items]
Contract revenues	46,993		46,993
Operating (loss) income	2,366		2,366
Depreciation and amortization expense	(2,592)		(2,592)
Total Assets	156,325		156,325
Property and equipment, net	$ 14,759		$ 14,759