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Organization, Business and Significant Accounting Policies (Details Textual) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Jan. 02, 2017
Organization Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Operating Income (Loss) |  |  |  |  |  |  |  |  |  |  | $ 29,558 | $ 38,754 | $ 44,841 |
Net Income (Loss) Attributable to Parent | $ 13,579 | [1] | $ 5,145 | $ 1,230 | $ 1,200 | $ 7,798 | [1] | $ 6,146 | $ 5,500 | $ 1,987 | $ 21,154 | $ 21,431 | $ 27,302 |
Earnings Per Share, Diluted | $ 0.82 | [1] | $ 0.31 | $ 0.07 | $ 0.07 | $ 0.48 | [1] | $ 0.38 | $ 0.31 | $ 0.10 | $ 1.28 | $ 1.23 | $ 1.30 |
Advertising Expense |  |  |  |  |  |  |  |  |  |  | $ 700 | $ 600 | $ 500 |
Self Insurance Reserve, Noncurrent | $ 32,225 |  |  |  |  | $ 32,092 |  |  |  |  | 32,225 | 32,092 |  |
Insurance Settlements Receivable, Noncurrent | 14,295 |  |  |  |  | 14,692 |  |  |  |  | 14,295 | 14,692 |  |
Income tax expense |  |  |  |  |  |  |  |  |  |  | 3,486 | 16,914 | $ 16,997 |
Retained Earnings (Accumulated Deficit) | 143,241 |  |  |  |  | $ 123,345 |  |  |  |  | 143,241 | $ 123,345 |  |
Significant Change Orders Or Claims [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revenues |  |  |  |  |  |  |  |  |  |  | 13,700 |  |  |
New Accounting Pronouncement, Early Adoption, Effect [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Income tax expense |  |  |  |  |  |  |  |  |  |  | 800 |  |  |
Maximum [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingency Insurance Policy Deductible for Each Line of Coverage Excluding Wildfire and Health | 1,000 |  |  |  |  |  |  |  |  |  | 1,000 |  |  |
Loss Contingency Insurance Policy Deductible for Wildfire | 2,000 |  |  |  |  |  |  |  |  |  | 2,000 |  |  |
Loss Contingency Health Insurance Deductible For Qualified Individuals | $ 200 |  |  |  |  |  |  |  |  |  | $ 200 |  |  |
Accounts Receivable [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  |  |  |  |  |  |  |  |  |  | 11.20% |  |
Accounts Receivable [Member] | Number of Customers [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  |  |  |  |  |  |  |  |  | 10.00% | 10.00% |  |
Revenues [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  |  |  |  |  |  |  |  |  | 40.40% | 46.40% | 44.60% |
Revenues [Member] | Number of Customers [Member] | Customer concentration risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  |  |  |  |  |  |  |  |  |  | 10.00% | 10.00% |
Labor employees covered by collective bargaining agreements [Member] | Labor Force Concentration Risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  |  |  |  |  |  |  |  |  | 91.00% |  |  |
Sales Revenue, Net [Member] | TD customer [Member] | Customer concentration risk [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Concentration Risk, Percentage |  |  |  |  |  |  |  |  |  |  | 10.70% |  |  |
Restatement Adjustment [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retained Earnings (Accumulated Deficit) |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 200
Estimate Adjustment [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization Consolidation and Presentation of Financial Statements [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cost Estimate Revision Gross Margin Increase (Decrease) Percentage |  |  |  |  |  |  |  |  |  |  | (0.70%) | (0.20%) | 0.50% |
Operating Income (Loss) |  |  |  |  |  |  |  |  |  |  | $ (10,400) | $ (2,600) | $ 5,900 |
Net Income (Loss) Attributable to Parent |  |  |  |  |  |  |  |  |  |  | $ (6,200) | $ (1,400) | $ 3,600 |
Earnings Per Share, Diluted |  |  |  |  |  |  |  |  |  |  | $ (0.38) | $ (0.08) | $ 0.17 |
[1] | Results for the fourth quarter of 2017 include a net Tax Act benefit of $7.8 million, or $0.48 and $0.47 per basic and diluted share, respectively. See further discussion in Note 10 — Income Taxes to our Financial Statements.

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