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Business Summary and Significant Accounting Policies - Narrative (Details)	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) segment	Sep. 30, 2017 USD ($) segment	Sep. 30, 2016 USD ($)	Apr. 03, 2017 USD ($)	Dec. 31, 2016 USD ($)
Business Acquisition [Line Items]
Number of reportable segments | segment			2	2
Ownership interest in joint venture				50.00%
Costs and estimated earnings in excess of billings
Business Acquisition [Line Items]
Unapproved change orders, amount	$ 300,000		$ 300,000	$ 300,000			$ 2,200,000
Contracts receivable, claims and uncertain amounts	10,500,000		10,500,000	10,500,000			9,200,000
Contracts receivable, unpaid project contract price	3,900,000		$ 3,900,000	3,900,000			$ 3,900,000
Operating income (Loss)
Business Acquisition [Line Items]
Estimated construction loss before tax	$ 1,300,000	$ (600,000)		$ 200,000	$ (1,100,000)
Minimum
Business Acquisition [Line Items]
Ownership interest in joint venture				50.00%
Revenue recognition, contract term				12 months
Warranty term				1 year
Maximum
Business Acquisition [Line Items]
Revenue recognition, contract term				36 months
Warranty term				2 years
Loan and security agreement | Term loan | Senior secured term loans
Business Acquisition [Line Items]
Debt instrument face amount						$ 85,000,000
Tealstone
Business Acquisition [Line Items]
Percentage of outstanding stock						100.00%

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