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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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