Business Acquisition - Pro Forma Results (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Business Acquisition [Line Items]
Contract revenues	$ 137,420	$ 140,301		$ 269,924
Costs of contract revenues	122,023	123,355		238,267
Gross profit	15,397	16,946		31,657
Selling, general and administrative expenses	17,528	16,899		32,437
(Gain) loss from sale of asset, net	335	(234)		(606)
Operating (loss) income from operations	(2,466)	281		(174)
Other income	11	9		22
Interest income	0	0		1
Interest expense	(1,462)	(1,600)		(3,117)
Other expense, net	(1,451)	(1,591)		(3,094)
Loss before income taxes	(3,917)	(1,310)		(3,268)
Income tax benefit	(1,624)	(502)		(1,252)
Net loss	$ (2,293)	$ (808)	$ (4,101)	$ (2,016)
Basic income (loss) per share (in dollars per share)	$ (0.08)	$ (0.03)		$ (0.07)
Diluted income (loss) per share (in dollars per share)	$ (0.08)	$ (0.03)		$ (0.07)
Basic (in shares)	27,941,814	27,464,683	27,867,090	27,383,748
Diluted (in shares)	27,941,814	27,464,683	27,867,090	27,383,748
Business Acquisition, Pro Forma Information [Abstract]
Business acquisition, pro forma revenue			$ 281,684	$ 287,000
Business acquisition, pro forma cost of revenue			253,120	254,021
Business acquisition, pro forma gross profit			28,564	32,979
Business cquisition, pro forma selling, general and administrative			33,251	33,108
Business acquisition, pro forma gain (loss) on disposition of assets			(177)	(606)
Business acquisition, pro forma operating income (loss)			(4,510)	477
Business acquisition, pro forma non-operating income (expense)			24	22
Business acquisition, pro forma interest Income, deposits with financial institutions			0	1
Business acquisition, pro forma interest expense			(2,817)	(3,117)
Business acquisition, pro forma other nonoperating income (expense)			(2,793)	(3,094)
Business acquisition, pro forma income (loss) from continuing operations before income taxes, extraordinary items, noncontrolling Interest			(7,303)	(2,617)
Business acquisition, pro forma income tax expense (benefit)			(2,839)	(1,024)
Business acquisition, pro forma net income (loss)			$ (4,464)	$ (1,593)
Business acquisition, pro forma earnings per share, basic (USD per share)			$ (0.16)	$ (0.06)
Businessa acquisition, pro forma earnings per share, diluted (USD per share)			$ (0.16)	$ (0.06)
Business acquisition, pro forma weighted average number of shares outstanding, basic (shares)			27,867,090	27,383,748
Business acquisition, pro forma weighted average number of shares, diluted (shares)			27,867,090	27,383,748
Federal statutory tax rate			35.00%	35.00%
Acquisition-related Costs
Business Acquisition [Line Items]
Contract revenues			$ 0	$ 0
Costs of contract revenues			0	0
Gross profit			0	0
Selling, general and administrative expenses			146	146
(Gain) loss from sale of asset, net			0	0
Operating (loss) income from operations			(146)	(146)
Other income			0	0
Interest income			0	0
Interest expense			10	18
Other expense, net			10	18
Loss before income taxes			(136)	(128)
Income tax benefit			(196)	228
Net loss			60	(356)
Orion Group Holdings, Inc.
Business Acquisition [Line Items]
Contract revenues			276,177
Costs of contract revenues			247,795
Gross profit			28,382
Selling, general and administrative expenses			32,507
(Gain) loss from sale of asset, net			(177)
Operating (loss) income from operations			(3,948)
Other income			21
Interest income			0
Interest expense			(2,817)
Other expense, net			(2,796)
Loss before income taxes			(6,744)
Income tax benefit			(2,643)
Net loss			$ (4,101)
Basic income (loss) per share (in dollars per share)			$ (0.15)
Diluted income (loss) per share (in dollars per share)			$ (0.15)
Basic (in shares)			27,867,090
Diluted (in shares)			27,867,090
TAS Commercial Concrete
Business Acquisition [Line Items]
Contract revenues			$ 5,507	17,076
Costs of contract revenues			5,325	15,754
Gross profit			182	1,322
Selling, general and administrative expenses			598	525
(Gain) loss from sale of asset, net			0	0
Operating (loss) income from operations			(416)	797
Other income			3	0
Interest income			0	0
Interest expense			(10)	(18)
Other expense, net			(7)	(18)
Loss before income taxes			(423)	779
Income tax benefit			0	0
Net loss			(423)	779
Consolidated Entities
Business Acquisition [Line Items]
Contract revenues			281,684	287,000
Costs of contract revenues			253,120	254,021
Gross profit			28,564	32,979
Selling, general and administrative expenses			33,105	32,962
(Gain) loss from sale of asset, net			(177)	(606)
Operating (loss) income from operations			(4,364)	623
Other income			24	22
Interest income			0	1
Interest expense			(2,827)	(3,135)
Other expense, net			(2,803)	(3,112)
Loss before income taxes			(7,167)	(2,489)
Income tax benefit			(2,643)	(1,252)
Net loss			$ (4,524)	$ (1,237)
Basic income (loss) per share (in dollars per share)			$ (0.16)	$ (0.05)
Diluted income (loss) per share (in dollars per share)			$ (0.16)	$ (0.05)
Basic (in shares)			27,867,090	27,383,748
Diluted (in shares)			27,867,090	27,383,748