Accounting Standards Effects of Adoption of ASC 606 and ASC 842 on Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts receivable, net	$ 105,067	$ 105,820	$ 135,687
Contract assets	77,188	63,810	0
Costs and estimated earnings in excess of billings on uncompleted contracts	0	0	32,698
Operating lease right-of-use assets	21,056	19,830	0
Deferred tax asset	4,786	4,176	4,409
Contract liabilities	42,370	48,816	0
Billings in excess of costs and estimated earnings on uncompleted contracts	0	0	50,843
Accrued expenses and other current liabilities	20,045	56,201	53,801
Current portion of long-term debt	4,425	3,203	3,141
Current operating lease liabilities	3,750	3,240	0
Long-term debt	38,868	23,679	23,614
Long-term operating lease liabilities	18,247	17,385	0
Other long-term liabilities	763	720	1,514
Accumulated deficit	(9,688)	(7,913)	$ (8,424)
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts receivable, net	0	0
Contract assets	0	0
Costs and estimated earnings in excess of billings on uncompleted contracts	0	0
Operating lease right-of-use assets	21,056	19,830
Deferred tax asset	0	0
Contract liabilities	0	0
Billings in excess of costs and estimated earnings on uncompleted contracts	0	0
Accrued expenses and other current liabilities	0	0
Current portion of long-term debt	60	62
Current operating lease liabilities	3,750	3,240
Long-term debt	66	65
Long-term operating lease liabilities	18,247	17,385
Other long-term liabilities	(939)	(794)
Accumulated deficit	(128)	(128)
Calculated under Revenue Guidance in Effect before Topic 606
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts receivable, net	137,940
Contract assets	(81)
Costs and estimated earnings in excess of billings on uncompleted contracts	43,033
Operating lease right-of-use assets	0
Deferred tax asset	5,194
Contract liabilities	316
Billings in excess of costs and estimated earnings on uncompleted contracts	45,076
Accrued expenses and other current liabilities	17,159
Current portion of long-term debt	4,365
Current operating lease liabilities	0
Long-term debt	38,802
Long-term operating lease liabilities	0
Other long-term liabilities	1,702
Accumulated deficit	(10,651)
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Accounts receivable, net	(32,873)	(29,867)
Contract assets	77,269	63,810
Costs and estimated earnings in excess of billings on uncompleted contracts	(43,033)	(32,698)
Operating lease right-of-use assets	0	0
Deferred tax asset	(408)	(233)
Contract liabilities	42,054	48,816
Billings in excess of costs and estimated earnings on uncompleted contracts	(45,076)	(50,843)
Accrued expenses and other current liabilities	2,886	2,400
Current portion of long-term debt	0	0
Current operating lease liabilities	0	0
Long-term debt	0	0
Long-term operating lease liabilities	0	0
Other long-term liabilities	0	0
Accumulated deficit	$ 1,091	$ 639