Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract receivables, net	$ 18,757		$ 13,997
Deferred tax assets	6,336		7,167	$ 7,167
Billings in excess of revenue earned	12,592		14,543
Accumulated Deficit	(43,711)		(42,870)
Contracts Revenue	22,895	$ 16,342
Gross Profit	4,898	4,122
(Benefit) provision for income taxes	259	73
Net Income (Loss) Attributable to Parent	(1,496)	(266)
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	0	$ 254
Restatement Adjustment [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract receivables, net			13,987
Deferred tax assets			6,926
Billings in excess of revenue earned			13,637
Accumulated Deficit			(42,215)
Difference between Revenue Guidance in Effect before and after Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract receivables, net	(117)		(10)
Deferred tax assets	(269)		(241)
Billings in excess of revenue earned	(1,056)		(906)
Accumulated Deficit	670		$ 655
Contracts Revenue	43
Gross Profit	43
(Benefit) provision for income taxes	(28)
Net Income (Loss) Attributable to Parent	15
Calculated under Revenue Guidance in Effect before Topic 606 [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract receivables, net	18,874
Deferred tax assets	6,605
Billings in excess of revenue earned	13,648
Accumulated Deficit	(44,381)
Contracts Revenue	22,852
Gross Profit	4,855
(Benefit) provision for income taxes	231
Net Income (Loss) Attributable to Parent	$ (1,511)