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Note 1 - Business Summary and Significant Accounting Policies (Details Textual) |  | 3 Months Ended | 6 Months Ended |
--- | --- | --- | --- | ---
Apr. 03, 2017 USD ($) | Jun. 30, 2017 USD ($) | Jun. 30, 2016 USD ($) | Jun. 30, 2017 USD ($) | Jun. 30, 2016 USD ($) | Dec. 31, 2016 USD ($)
Number of Reportable Segments | 2 |  |  | 2 |  |
Ownership Interest in Joint Venture |  |  |  | 50.00% |  |
Costs and Estimated Earnings in Excess of Billings [Member] |  |  |  |  |  |
Contracts Receivable, Claims and Uncertain Amounts |  | $ 12,000,000 |  | $ 12,000,000 |  | $ 9,200,000
Contracts Receivable, Unpaid Project Contract Price |  | 3,900,000 |  | 3,900,000 |  | 3,900,000
Unapproved Change Orders, Amount |  | 1,400,000 |  | 1,400,000 |  | $ 2,200,000
Operating Income (Loss) [Member] |  |  |  |  |  |
Estimated Construction Gross (Loss) Profit, Before Tax |  | $ 1,800,000 | $ 700,000 | $ 1,100,000 | $ (500,000) |
Minimum [Member] |  |  |  |  |  |
Ownership Interest in Joint Venture |  |  |  | 50.00% |  |
Revenue Recognition Percentage of Completion Range |  |  |  | 12 years |  |
Warranty Term |  |  |  | 1 year |  |
Maximum [Member] |  |  |  |  |  |
Revenue Recognition Percentage of Completion Range |  |  |  | 36 years |  |
Warranty Term |  |  |  | 2 years |  |
Loan and Security Agreement [Member] | Wilmington Trust, National Association [Member] | Senior Secured Term Loans [Member] |  |  |  |  |  |
Debt Instrument, Face Amount | $ 85,000,000 |  |  |  |  |
Tealstone Construction [Member] |  |  |  |  |  |
Business Acquisition, Percentage of Voting Interests Acquired | 100.00% |  |  |  |  |

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