Segment Information - Summary (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Segment Reporting Information [Line Items]
Contract revenues	$ 99,211	$ 125,073	$ 159,767	$ 136,843	$ 162,214	$ 140,162	$ 137,420	$ 138,757	$ 520,894	$ 578,553	$ 578,236
Operating (loss) income	(104,795)	$ (7,405)	$ 4,591	$ 7,069	10,840	$ (5,354)	$ (2,466)	$ (1,482)	(100,540)	1,538	4,074
Depreciation and amortization									(31,799)	(29,491)	$ (34,162)
Assets	312,870				433,285				312,870	433,285
Property and equipment, net	148,003				146,278				148,003	146,278
Heavy Civil Marine Construction Segment
Segment Reporting Information [Line Items]
Contract revenues									243,883
Commercial Concrete Segment
Segment Reporting Information [Line Items]
Contract revenues									277,011
Operating Segments | Heavy Civil Marine Construction Segment
Segment Reporting Information [Line Items]
Contract revenues									243,883	285,736
Operating (loss) income									(61,012)	(18,406)
Depreciation and amortization									(22,657)	(20,370)
Assets	190,503				260,935				190,503	260,935
Property and equipment, net	128,168				128,421				128,168	128,421
Operating Segments | Commercial Concrete Segment
Segment Reporting Information [Line Items]
Contract revenues									277,011	292,817
Operating (loss) income									(39,528)	19,944
Depreciation and amortization									(9,142)	(9,121)
Assets	122,367				172,350				122,367	172,350
Property and equipment, net	$ 19,835				$ 17,857				$ 19,835	$ 17,857