Segment Information - Summary (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Contract revenues	$ 144,295	$ 164,017	$ 140,301	$ 129,623	$ 161,891	$ 137,061	$ 86,091	$ 81,455	$ 578,236	$ 466,498	$ 385,818
Operating income (loss)	(5,283)	$ 9,531	$ 281	$ (455)	3,231	$ (8,325)	$ (2,712)	$ (193)	4,074	(7,999)	10,262
Depreciation and amortization									(34,162)	(28,083)	$ (23,451)
Assets	447,676				461,462				447,676	461,462
Property and equipment, net	158,082				165,989				158,082	165,989
Operating Segments | Heavy Civil Marine Construction Segment
Segment Reporting Information [Line Items]
Contract revenues									284,632	347,117
Operating income (loss)									(12,403)	(14,243)
Depreciation and amortization									(21,398)	(21,075)
Assets	279,362				315,869				279,362	315,869
Property and equipment, net	143,425				150,117				143,425	150,117
Operating Segments | Commercial Concrete Segment
Segment Reporting Information [Line Items]
Contract revenues									293,604	119,381
Operating income (loss)									16,477	6,244
Depreciation and amortization									(12,764)	(7,008)
Assets	168,314				145,593				168,314	145,593
Property and equipment, net	$ 14,657				$ 15,872				$ 14,657	$ 15,872