Schedule of Roll Forward Activity in Insurance Reserves [Table Text Block] Schedule of roll forward activity in the insurance reserve Tabular disclosure of roll forward activity in the insurance reserve. Operating lease, additional disclosure Operating Lease, Additional Disclosure [Abstract] Threshold Limit of Rent Period for Including in Rent Expense Threshold period of rent Represents the threshold limit of period of rent for including in rental expense. Loss Contingency, Insurance Expense Insurance expense Represents the insurance expenses, including premiums, for workers' compensation, general liability, automobile liability and employee health benefits. Number of Executive Officers with whom Employment Agreements Entered Number of executive officers Represents the number of executive officers with whom the employment agreement was entered into by the entity. Share Based Compensation Arrangement by Share Based Payment Award, Options, Aggregate Intrinsic Value [Abstract] Aggregate Intrinsic Value Award Type [Axis] Share Based Compensation Arrangement by Share Based Payment Award, Options, Vested in Period, Total Fair Value Fair value of options vested (in dollars) The total fair value of stock options vested during the reporting period. Exercise Price Ranges, $3.65-$9.00 Represents the range of exercise price from 3.65 dollars per share to 9.00 dollars per share. Range of Exercise Prices from Dollars 3.65 to 9.00 [Member] Range of Exercise Price from Dollars 9.01 to 18.00 [Member] Exercise Price Ranges, $9.01-$18.00 Represents the range of exercise price from 9.01 dollars per share to 18.00 dollars per share. Range of Exercise Prices from Dollars 18.01 to 24.18 [Member] Exercise Price Ranges, $18.01-$24.18 Represents the range of exercise price from 18.01 dollars per share to 24.18 dollars per share. Amendment Description Share Based Compensation Shares Authorized under Stock Option Plans, Exercise Price Range Outstanding Options [Abstract] Options Outstanding Amendment Flag Share Based Compensation Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options [Abstract] Options Exercisable Share Based Compensation Arrangement by Share Based Payment Award, Potential Payout as Percentage of Target Shares Potential payout as a percentage of target shares The percentage of target shares, an employee can earn, under the plan. Share Based Compensation Arrangement by Share Based Payment Award, Equity Instruments Other than Option, Average Period Used for Calculation of Performance Goals Based on Return on Equity Vesting period for calculating performance goals based on average return on equity Represents the vesting period for calculation of performance goals based on return on equity. Share Based Compensation Arrangement by Share Based Payment Award, Award, Percentage of Return on Equity Return on equity for the performance period (as a percent) Represents the percentage of return on equity for the performance period. Share Based Compensation Arrangement by Share Based Payment Award, Exercisable Period from Date of Grant Exercisable period from date of grant Represents the period, from the date of grant, that award can be exercised once they have vested. Schedule of Defined Contribution Plans [Table] Disclosures about defined contribution plans. Defined Contribution Plans [Axis] Information by defined contribution plans. Syndicated Credit Agreement [Member] Credit Agreement A contractual arrangement with a lender consisting of a syndicated credit agreement. Swingline Loans [Member] Swingline loans Represents information pertaining to the swingline loan, a loan that grants institutions access to large amounts of cash in order to cover possible shortfalls from other debt commitments. Debt Instrument Variable Rate Base [Axis] The alternative reference rates that may be used to calculate the variable interest rate of the debt instrument. Debt Instrument Variable Rate Base [Domain] Identification of the reference rate that is used to calculate the variable interest rate of the debt instrument. Debt Instrument Variable Rate Base, Alternate Base Rate [Member] ABR The alternate base rate used to calculate the variable interest rate of the debt instrument. Debt Instrument Variable Rate, Base Prime Rate [Member] Prime Rate The prime rate used to calculate the variable interest rate of the debt instrument. Debt Instrument Variable Rate Base, Federal Funds Effective Rate [Member] Federal Funds Effective Rate The federal funds effective rate used to calculate the variable interest rate of the debt instrument. Debt Instrument Variable Rate Base LIBOR Rate [Member] LIBOR rate The London Interbank Offered Rate (LIBOR) used to calculate the variable interest rate of the debt instrument. Debt Instrument Term Term of the credit agreement Represents the term of the credit agreement. Current Fiscal Year End Date Line of Credit Facility Option to Increase Maximum Borrowing Capacity Option to increase borrowing capacity Represents the option to increase maximum borrowings on the credit facility. Letter of Credit Fees Percentage Letter of credit fee (as a percent) Represents the fees for the letter of credit facility, expressed as a percentage. Letter of Credit Fronting Fees Facing fees (as a percent) The percentage of fronting fees paid on the outstanding amount of letters of credit. Schedule of Deferred Tax Assets and Liabilities, Balance Sheet Classification [Table Text Block] Schedule of balance sheet classification of deferred income taxes Tabular disclosure of the balance sheet classification of deferred income taxes. Effective Income Tax Rate Reconciliation Provision to Return Adjustments Net Provision to return adjustments, net (as a percent) The sum of the differences between the effective income tax rate and domestic federal statutory income tax rate attributable to provision to return adjustments. Income Tax Examination Federal Income Tax Settlements Period under Examination Period under examination Represents the period for which the entity's federal tax returns are subject to examination. Unrecognized Tax Benefits Including Tax Interest Accrued Total liability for unrecognized tax benefits The gross amount of unrecognized tax benefits, including interest, pertaining to uncertain tax positions taken in tax returns as of the balance sheet date. Schedule of Intangible Assets and Goodwill [Table] Disclosure of goodwill and intangible assets, which may be broken down by segment or major class. Schedule of Intangible Assets and Goodwill [Line Items] Goodwill and Other Intangible Assets Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Additional Information of Intangible Assets [Abstract] Additional information on intangible assets Stock Issued Shares in Lieu of Director Retainer Stock issued in lieu of director retainer (in shares) Represents the number of shares issued in lieu of director retainer. Document Period End Date Organization and Business Basis of Presentation Basis of Presentation, Significant Accounting Policies and New Accounting Pronouncements [Text Block] Basis of Presentation This element aggregates basis of presentation, significant accounting policies, and new accounting pronouncements into a single block of text. Document and Entity Information Cash and Deemed Dividends Cash and Deemed Dividends Disclosure [Text Block] Cash and Deemed Dividends The entire disclosure for dividends declared and paid as of the financial reporting date. New Accounting Pronouncements [Text Block] Recently Issued and Adopted Accounting Pronouncements The entire disclosure for new accounting pronouncements that have been issued but not yet adopted, and new accounting pronouncements adopted. Stock Repurchased During Period Value Payroll Tax Withholding Return of shares in lieu of payroll tax withholding Equity impact of the value of stock that has been repurchased during the period and has not been retired and is held in treasury. Stock issued in lieu of director retainer Stock Issued in Lieu of Director Retainer This element represents the amount of Stock issued in lieu of director retainer. Entity [Domain] Number of operating subsidiaries Represents the number of operating subsidiaries of the entity. Number of Operating Subsidiaries Schedule of net asset position for contracts in process Tabular disclosure of costs and estimated earnings on uncompleted contracts, from their inception, and related amounts billed. Long Term Contracts or Programs [Table Text Block] Tabular disclosure of the net of 1) costs and estimated earnings in excess of related billings on uncompleted contracts and 2) billings in excess of costs and estimated earnings on uncompleted contracts included in the consolidated balance sheet. Long Term Contracts or Programs Net Costs and Estimated Earnings in Excess of Billings [Table Text Block] Schedule of net asset position for contracts in process included in consolidated balance sheet Net asset position for contracts in process Costs and Estimated Earnings on Uncompleted Contracts or Programs [Abstract] Costs incurred on uncompleted contracts Represents the costs incurred on uncompleted contracts. Costs Incurred on Uncompleted Contracts Represents the estimated earnings on uncompleted contracts. Estimated Earnings Estimated earnings Costs and estimated earnings on uncompleted contracts Represents the aggregate of costs incurred on uncompleted contracts and estimated earnings. Aggregate Costs Incurred on Uncompleted Contracts and Estimated Earnings Less: Billings to date Represents the billings to date on uncompleted contracts accounted for under the percentage-of-completion method. Billings to Date Net costs and estimated earnings in excess of billings Represents the net costs and estimated earnings in excess of billings on uncompleted contracts accounted for under the percentage-of-completion method. Net Costs and Estimated Earnings in Excess of Billings Term of operating lease Represents the term of the operating lease arrangements of the entity. Operating Lease Term Number of irrevocable standby letters of credit outstanding Represents the number of irrevocable standby letters of credit outstanding. Number of Letters of Credit Outstanding Represents the number of letters of credit related to the payment obligation under insurance programs. Number of Letters of Credit Outstanding Related to Payment Obligation under Insurance Programs Number of letters of credit related to the payment obligation under insurance programs Letters of credit outstanding related to contract performance obligations Represents the amount of the letters of credit related to contract performance obligations. Letters of Credit Outstanding Amount Related to Contract Performance Obligations Letters of credit outstanding related to the payment obligation under insurance programs Letters of Credit Outstanding Amount Related to Payment Obligation under Insurance Programs Represents the letters of credit outstanding related to the payment obligation under insurance programs. Deductible per claim for each line of coverage, until claim aggregate is reached Represents the amount of deductible up to the claim aggregate under insurance arrangements, for each line of coverage excluding medical insurance. Loss Contingency Insurance Policy Deductible for Each Line of Coverage Deductible per claim, once a policy's claim aggregate is reached per line of coverage Represents the amount of deductible under insurance arrangements, once the policy's claim aggregate is reached for each line of coverage, excluding medical insurance. Loss Contingency Insurance Policy Deductible if Claim Aggregate Reached Per Line of Coverage Deductible under health insurance benefits for qualified individuals Represents the amount of deductible under health insurance benefits for qualified individuals. Loss Contingency Health Insurance Deductible for Qualified Individuals Purchase Commitments for Construction Equipment Purchase Commitments [Abstract] Represents the retainer share election program related to common stock, under which each of the Company's independent directors receives a retainer to be paid annually in cash or at the option of the director, in form of common stock. Retainer Share Election Program [Member] Retainer Share Election Program Employees [Member] Various employees Represents the various employees, which may include the company's named executive officers. LTIP Represents information pertaining to the 2007 Long-term Incentive Plan. Long Term Incentive Plan 2007 [Member] Number of stock-based compensation plans Represents the number of share-based compensation plans approved by the entity's shareholders. Share Based Compensation Arrangement by Share Based Payment Award Number of Plans Represents the number of employees to whom awards on other than stock (or unit) option plans are granted. Share Based Compensation Arrangement by Share Based Payment Award Equity Instruments Other than Options Number of Employees to Whom Granted Number of employees to whom awards covering shares of common stock granted Number of prior grants from which shares became vested and taxable to individual holders Represents the number of prior grants from which awards on other than stock (or unit) option plans became vested. Share Based Compensation Arrangement by Share Based Payment Award Equity Instruments Other than Options Number of Prior Grants from which Awards Vested Net reduction in expense related to a change in the estimated forfeiture rates for the various awards and a change in the estimated number of performance shares that are expected to be earned (in dollars) Represents the net reduction in expense related to a change in the estimated forfeiture rates for the various awards and a change in the estimated number of performance shares that are expected to be earned. Allocated Share Based Compensation Expense Net Reduction for Change in Estimated Forfeiture Rates and Change in Performance Shares Expected to be Earned Transmission and Distribution [Member] T&D Represents the Transmission and Distribution ("T&D"), a reportable segment of the entity. C&I Represents the Commercial and Industrial ("C&I"), a reportable segment of the entity. Commercial and Industrial [Member] Number of Multiemployer Plans Withdrawal that Could Result in Assessment of Additional Contribution Liabilities Related to Underfunding of Plans Minimum Number of multi-employer pension plans, the withdrawal of which could result in assessment of liabilities for additional contributions related to the underfunding of plans, minimum Represents the minimum number of multi-employer pension plans from the withdrawal of which a subsidiary could be assessed for liabilities for additional contributions related to the underfunding of plans. Potential Adverse Outcome Number of Litigation Claims Minimum Potential number of litigation claims in which an adverse outcome could result, minimum Represents the minimum potential number of litigation claims in which an adverse outcome could result. Scheduled period of time for cash outlay requirements Represents the schedule period of time for cash outlay requirements under an existing purchase commitment. Significant Purchase Commitment, Scheduled Period of Time for Cash Outlay Insurance [Policy Text Block] Insurance Describes an entity's accounting policy for insurance. Maximum Warranty Period Warranty period, maximum Represents the maximum term of warranty typically provided to customers. Accounts Receivable, Maximum Collection Period of Majority of Customer Balances Maximum collection period of majority of customer balances Represents the maximum accounts receivable period within which majority of customer balances are collected. Minimum Term of Some Larger Contracts Minimum term of some larger contracts Represents the minimum term of some larger contracts. Classification of Construction Contract [Abstract] Classification of Construction Contract-related Assets and Liabilities Building, Building Improvements and Land Improvements [Member] Buildings and improvements, including land improvements Facility held for productive use including, but not limited to, office, production, storage and distribution facilities and any addition, improvement, or renovation to the structure, for example, but not limited to, interior masonry, interior flooring, electrical, and plumbing. Also including additions or improvements to real estate held. Buildings and improvements Construction Equipment [Member] Construction equipment Represents the construction equipment, including large tool purchases. Insurance Policies [Table] Tabular disclosure representing information related to insurance policies. Insurance Policies [Line Items] Insurance Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Insurance Policies, Deductible Per Claim for Each Line of Coverage Deductible for each line of coverage Amount of risk retained by the entity per claim before the insurance arrangement begins to provide coverage for each line of coverage under insurance arrangements. Insurance Policies, Deductible if Claim Aggregate Reaches Per Line of Coverage Deductible for policies whose claim aggregate reaches per line of coverage Represents the amount of deductible for policies whose claim aggregate reaches per line of coverage. Health Insurance, Deductible for Qualified Individuals Deductible under health insurance benefits for qualified individuals Represents the amount of deductible under health insurance benefits for qualified individuals. One Largest Customer [Member] One customer Represents one largest customer in relation to accounts receivable of the entity. Summary of Significant Accounting Policies Two Largest Customer [Member] Two customers Represents two largest customers in relation to accounts receivable of the entity. Ten Largest Customer [Member] Ten customers Represents ten largest customers in relation to revenues of the entity. Entity Well-known Seasoned Issuer Dominion Resources Inc [Member] Dominion Resources, Inc. Represents Dominion Resources Inc., one of the customers of the entity. Entity Voluntary Filers National Grid [Member] National Grid Represents National Grid, one of the customers of the entity. Entity Current Reporting Status Number of Customers, Individually Exceeding 10 Percent Consolidated Accounts Receivable Number of customers individually exceeding 10.0% of consolidated accounts receivable Represents the number of customers individually exceeding 10 percent of consolidated accounts receivable. Entity Filer Category Schedule of Roll Forward Activity of Allowance for Doubtful Accounts [Table Text Block] Schedule of roll-forward activity of allowance for doubtful accounts Tabular disclosure of roll-forward activity of allowance for doubtful accounts during the period. Entity Public Float Intangible Assets, Gross, Including Goodwill Gross carrying amount of goodwill and other intangible assets Gross amount of finite-lived intangible assets, indefinite-lived intangible assets and goodwill. Entity Registrant Name Defined Contribution Plans [Domain] The name of the defined contribution plan or a description of the plans grouped. Entity Central Index Key Profit Sharing and Thrift Employee Benefit Plan [Member] Profit sharing and thrift employee benefit plan Represents information pertaining to profit sharing and thrift employee benefit plan in effect for all eligible salaried employees. Employee Benefit Plan [Member] Employee benefit plan Represents information pertaining to employee benefit plan in effect for certain non-union hourly employees. Defined Contribution Plans [Line Items] Defined contribution plan Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. National Electrical Annuity Plan [Member] National Electrical Annuity Plan Represents information pertaining to national electrical annuity plan. Entity Common Stock, Shares Outstanding Eighth District Electrical Pension Fund Annuity Plan [Member] Eighth District Electrical Pension Fund Annuity Plan Represents information pertaining to eighth district electrical pension fund annuity plan. National Electrical Benefit Fund [Member] National Electrical Benefit Fund Represents information pertaining to national electrical pension fund. Eighth District Electrical Pension Fund [Member] Eighth District Electrical Pension Fund Represents information pertaining to eighth district electrical pension fund. IBEW Local 1249 Pension Plan [Member] IBEW Local 1249 Pension Plan Represents information pertaining to IBEW Local 1249 Pension Plan. Number of Locals Covered under Multiemployer Defined Plans Number of local unions Represents information pertaining to number of locals covered under multiemployer defined plan. Multiemployer Plans, Red Zone Funded Status, Percentage Percentage funded for red zone Represents the percentage funded for red zone status. Multiemployer Plans, Yellow Zone Funded Status, Percentage Percentage funded for yellow zone Represents the percentage funded for yellow zone status. Accounts Payable and Accrued Liabilities Disclosure [Text Block] Accrued Liabilities Multiemployer Plans, Green Zone Funded Status, Percentage Percentage funded for green zone Represents the percentage funded for green zone status. Minimum Extended Period of Contracting Cycle for Long Term Contracts Minimum extended period of contracting cycle for long-term contracts Represents the minimum extended period of contracting cycle for certain long-term contracts. Minimum Extended Period for Collection of Retainage on Certain Long Term Contracts Minimum extended period for collection of retainage on certain long-term contracts Represents the minimum extended period for collection of retainage on certain long-term contracts. Percentage of Retainage Recorded Percentage of retainage recorded and expected to be collected within one year Represents the percentage of retainage of long-term contracts recorded and expected to be collected by the entity within one year. Represents the maximum period within which the retainage recorded will be collected. Retainage Recorded Maximum Collection Period Maximum collection period of retainage recorded Real Estate Lease Term Real estate lease term Represents the real estate maximum lease term. Debt Instrument Covenant Leveraged Debt Ratio Leveraged debt ratio Represents the maximum leveraged debt ratio under the credit agreement. Debt Instrument Covenant Interest Coverage Ratio Interest coverage ratio Represent the minimum interest coverage ratio under the credit agreement. Volatility Period Over Which Common Stock Publicly Traded Volatility period over which the entity's common stock was publicly traded Represents the volatility period over which the entity's common stock was publicly traded prior to grants. Schedule of Segment Reporting Information Related to Allocation of Depreciation and Amortization by Segment[Text Block] Schedule of an allocation of total depreciation, including depreciation of shared construction equipment, and amortization Tabular disclosure of total depreciation and amortization for each reportable segment. Document Fiscal Year Focus Document Fiscal Period Focus Legal Entity [Axis] Document Type Accounts Receivable, Net, Current Accounts receivable, net of allowances of $1,305 and $1,078, respectively Accounts receivable, net current Accounts Receivable, Gross, Current Accounts receivable, gross current Accounts Payable, Current Accounts payable Accounts, Notes, Loans and Financing Receivable, Net, Current [Abstract] Accounts Receivable Accounts receivable Accounts Receivable [Member] Accounts Receivable and Allowance for Doubtful Accounts Accounts Receivable, Net [Abstract] Taxes, other than income taxes Accrual for Taxes Other than Income Taxes, Current Accrued income taxes Accrued Income Taxes, Current Payroll and incentive compensation Accrued Employee Benefits, Current Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property and equipment, accumulated depreciation (in dollars) Less: Accumulated depreciation and amortization Additional paid-in capital Additional Paid in Capital, Common Stock Additional Paid-In Capital Additional Paid-in Capital [Member] Tax benefit from stock-based awards Adjustment to Additional Paid in Capital, Income Tax Effect from Share-based Compensation, Net Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to net cash flows provided by operating activities- Stock-based compensation expense Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Advertising costs Advertising Expense Advertising Advertising Costs, Policy [Policy Text Block] Allocated Share-based Compensation Expense Stock-based compensation expense recognized (in dollars) Allowance for Doubtful Accounts Receivable, Current Accounts receivable, allowances (in dollars) Less: Allowance for doubtful accounts Allowance for Doubtful Accounts Receivable Balance at beginning of period Balance at end of period Allowance for Doubtful Accounts Receivable [Roll Forward] Roll-forward activity of allowance for doubtful accounts Allowance for Doubtful Accounts Receivable, Charge-offs Write offs, net of recoveries Amortization of Intangible Assets Amortization of intangible assets Amortization expense Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Anti-dilutive shares excluded from the diluted earnings per share calculation Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Earnings Per Share Antidilutive Securities, Name [Domain] Antidilutive Securities [Axis] Assets, Current [Abstract] Current assets Assets [Abstract] ASSETS Assets, Current Total current assets Assets Total assets Assets Billings in Excess of Cost, Current Billings in excess of costs and estimated earnings on uncompleted contracts Billings in excess of costs and estimated earnings on uncompleted contracts Contracts in Process Acquisition of property and equipment for which payment is pending Capital Expenditures Incurred but Not yet Paid Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents Beginning of period End of period Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Cash and Cash Equivalents, at Carrying Value [Abstract] Cash and cash equivalents: Cash Flow, Supplemental Disclosures [Text Block] Supplemental Cash Flows Chief Financial Officer [Member] Chief financial officer Commitments and Contingencies Commitments Contingencies and Guarantees [Text Block] Commitments and Contingencies Commitments and Contingencies. Commitments and contingencies Common Stock Common Stock [Member] Common Stock, Shares, Outstanding Common stock, outstanding shares Beginning balances (in shares) Ending balances (in shares) Common Stock, Shares, Issued Common stock, issued shares Common Stock, Value, Outstanding Common stock-$0.01 par value per share; 100,000,000 authorized shares; 20,747,161 and 20,405,044 shares issued and outstanding at December 31, 2012 and 2011, respectively Common Stock, Par or Stated Value Per Share Common stock, par value (in dollars per share) Common Stock, Shares Authorized Common stock, authorized shares Employee Benefit Plans Concentration Risk Type [Domain] Concentrations Concentration Risk [Line Items] Concentration Risk Benchmark [Domain] Concentration Risk [Table] Concentration Risk Benchmark [Axis] Concentrations Concentration Risk, Credit Risk, Policy [Policy Text Block] Concentration Risk Type [Axis] Percentage of concentration risk Concentration Risk, Percentage Consolidation Consolidation, Policy [Policy Text Block] Classification of Construction Contract-related Assets and Liabilities Construction Contractors, Policy [Policy Text Block] Contract Receivable Retainage, Due in Next Twelve Months Contract retainages Contract Receivable, Due in Next Twelve Months Contract receivables General Corporate Other Corporate [Member] Cost of Services Contract costs Costs in Excess of Billings on Uncompleted Contracts or Programs [Abstract] Net asset position for contracts in process Costs in Excess of Billings on Uncompleted Contracts or Programs Expected to be Collected within One Year Costs and estimated earnings in excess of billings on uncompleted contracts Costs and estimated earnings in excess of billings on uncompleted contracts Concentrations of credit risk Credit Concentration Risk [Member] State Current State and Local Tax Expense (Benefit) Current Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Current Income tax expense (benefit), Total Current Income Tax Expense (Benefit) Federal Current Federal Tax Expense (Benefit) Customer concentration risk Customer Concentration Risk [Member] Customer relationships Customer Relationships [Member] Variable rate basis Debt Instrument, Description of Variable Rate Basis Debt and Borrowing Arrangements Debt Instrument [Line Items] Schedule of Long-term Debt Instruments [Table] Debt Disclosure [Text Block] Debt and Borrowing Arrangements Debt and Borrowing Arrangements Interest rate margin (as a percent) Debt Instrument, Basis Spread on Variable Rate Debt Instrument [Axis] Debt Instrument, Name [Domain] Title of Individual [Axis] Deferred income tax liabilities: Deferred Tax Liabilities, Net [Abstract] Federal Deferred Federal Income Tax Expense (Benefit) Deferred Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Total deferred income tax liabilities Deferred Tax Liabilities, Gross Deferred Income Tax Expense (Benefit) Deferred income taxes Deferred Income tax expense (benefit), Total Total deferred income tax assets Deferred Tax Assets, Net of Valuation Allowance Balance sheet classification of deferred income taxes Deferred Tax Assets, Net of Valuation Allowance, Classification [Abstract] Deferred income tax assets: Deferred Tax Assets, Net [Abstract] Deferred Tax Assets, Net of Valuation Allowance, Current Deferred income tax assets Current deferred income tax assets State Deferred State and Local Income Tax Expense (Benefit) Other Deferred Tax Assets, Other Contract loss reserves Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Loss Reserves Stock-based awards Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Self insurance reserves Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Self Insurance Net deferred income taxes Deferred Tax Liabilities, Net Deferred Tax Liabilities, Net, Noncurrent Deferred income tax liabilities Non-current deferred income tax liabilities Intangible assets-tax over book amortization Deferred Tax Liabilities, Intangible Assets Property and equipment-tax over book depreciation Deferred Tax Liabilities, Property, Plant and Equipment Contributions Defined Contribution Plan, Cost Recognized Depreciation and amortization Depreciation, Depletion and Amortization Depreciation Depreciation and amortization of property and equipment Depreciation and amortization expense Director [Member] Eligible members of the Board of Directors Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Stock-Based Compensation Stock-Based Compensation Earnings Per Share, Diluted -Diluted (in dollars per share) Income per common share, diluted (in dollars per share) Diluted earnings per share (in dollars per share) Earnings Per Share, Basic and Diluted [Abstract] Earnings per share Earnings Per Share, Basic -Basic (in dollars per share) Income per common share, basic (in dollars per share) Basic earnings per share (in dollars per share) Earnings Per Share [Text Block] Earnings Per Share Earnings Per Share Earnings Per Share, Policy [Policy Text Block] Earnings Per Share Income per common share: Differences between the U.S. federal statutory rate and the Company's effective tax rate for continuing operations Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract] Total (as a percent) Effective Income Tax Rate, Continuing Operations Refund of fine related to OSHA violation (as a percent) Effective Income Tax Rate Reconciliation, Tax Settlements Non-deductible meals and entertainment (as a percent) Effective Income Tax Rate Reconciliation, Nondeductible Expense, Meals and Entertainment Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate U.S federal statutory rate (as a percent) Research and development credit (as a percent) Effective Income Tax Rate Reconciliation, Tax Credits, Research State income taxes, net of U.S. federal income tax expense (as a percent) Effective Income Tax Rate Reconciliation, State and Local Income Taxes Deferred tax adjustments, net (as a percent) Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance Domestic production/manufacturing deduction (as a percent) Effective Income Tax Rate Reconciliation, Deductions, Qualified Production Activities Other, net (as a percent) Effective Income Tax Rate Reconciliation, Other Adjustments Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition Weighted average vesting period Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] Other information Employee stock options Employee Stock Option [Member] Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized Total unrecognized stock-based compensation expense, net of estimated forfeitures (in dollars) Cash received from option exercises (in dollars) Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options Excess tax benefit (in dollars) Employee Service Share-based Compensation, Tax Benefit Realized from Exercise of Stock Options Employment agreements Employment Contracts [Member] Stockholders' Equity Equity Issuance, Per Share Amount Fair value of stock issued to independent directors for annual retainer (in dollars per share) Equity Component [Domain] Excess Tax Benefit (Tax Deficiency) from Share-based Compensation, Financing Activities Excess tax benefit from stock-based awards Excess Tax Benefit (Tax Deficiency) from Share-based Compensation, Operating Activities Excess tax benefit from stock-based awards Excess tax benefit from stock-based awards Executive Officer [Member] Executive officers Fair Value Measurements Fair Value Measurements Fair Value Disclosures [Text Block] Estimated useful life Finite-Lived Intangible Asset, Useful Life Finite-Lived Intangible Assets, Major Class Name [Domain] 2017 Finite-Lived Intangible Assets, Amortization Expense, Year Five Gross carrying amount of finite-lived intangible assets Finite-Lived Intangible Assets, Gross 2015 Finite-Lived Intangible Assets, Amortization Expense, Year Three Intangible asset amortization expense Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Accumulated Amortization Intangible assets, accumulated amortization (in dollars) Accumulated Amortization Remaining amortization period Finite-Lived Intangible Assets, Remaining Amortization Period 2013 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months 2016 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2014 Finite-Lived Intangible Assets, Amortization Expense, Year Two Gain (Loss) on Sale of Property Plant Equipment Gain on sale of property and equipment Goodwill Goodwill Gross carrying amount of goodwill Goodwill and Other Intangible Assets Goodwill and Intangible Assets, Policy [Policy Text Block] Goodwill and Intangible Assets Disclosure [Text Block] Goodwill and Intangible Assets Goodwill and Intangible Assets Gross Profit Gross profit Gross profit Impairment of Long-Lived Assets Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] Income Tax Contingency [Table] CONSOLIDATED STATEMENTS OF OPERATIONS Income Tax Disclosure [Text Block] Income Taxes Income Taxes Unrecognized tax benefits Income Tax Contingency [Line Items] Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest Income before provision for income taxes Income Tax Expense (Benefit) Income tax expense Income tax expense Income Taxes Receivable, Current Refundable income taxes Income Taxes Income Tax, Policy [Policy Text Block] Income Taxes Paid Income taxes Accounts payable Increase (Decrease) in Accounts Payable Billings in excess of costs and estimated earnings on uncompleted contracts Increase (Decrease) in Billing in Excess of Cost of Earnings Increase (Decrease) in Self Insurance Reserve Accrued self insurance Increase (Decrease) in Accounts Receivable Accounts receivable, net Increase (Decrease) in Operating Capital [Abstract] Changes in operating assets and liabilities Increase (Decrease) in Other Operating Assets Other assets Increase (Decrease) in Inventories Construction materials inventory Increase (Decrease) in Other Operating Liabilities Other liabilities Increase (Decrease) in Insurance Settlements Receivable Receivable for insurance claims in excess of deductibles Increase (Decrease) in Unbilled Receivables Costs and estimated earnings in excess of billings on uncompleted contracts Costs and estimated earnings in excess of billings on uncompleted contracts Increase (Decrease) in Stockholders Equity Increase (Decrease) in Stockholders' Equity [Roll Forward] Changes in outstanding shares of common stock Indefinite-lived intangible trademarks Indefinite-Lived Trademarks Insurance Claims [Member] Insurance and Claims Accruals Insurance Settlements Receivable Receivable for insurance claims in excess of deductibles Intangible Assets, Net (Excluding Goodwill) Intangible assets, net of accumulated amortization of $2,558 and $2,223, respectively Net carrying amount of goodwill and other intangible assets Intangible Assets, Net (Including Goodwill) Interest Expense Interest expense Interest Paid, Net Interest expense Construction Materials Inventory Inventory, Policy [Policy Text Block] Construction Materials Inventory Inventory, Raw Materials and Supplies, Net of Reserves [Abstract] Inventory, Raw Materials and Supplies, Net of Reserves Construction materials inventory Investment Income, Interest Interest income Letters of credit outstanding Letters of Credit Outstanding, Amount Long-term Debt, Type [Domain] Long-term Debt, Type [Axis] Field labor employees Labor Force Concentration Risk [Member] Land Land [Member] Rent expense Operating Leases, Rent Expense Letter of credit Letter of Credit [Member] Liabilities, Current Total current liabilities Liabilities, Current [Abstract] Current liabilities Liabilities Total liabilities Liabilities and Equity [Abstract] LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity Total liabilities and stockholders' equity Maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Commitment fee on unused portion of facility (as a percent) Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Interest rate (as a percent) Line of Credit Facility, Interest Rate at Period End Remaining borrowing capacity Line of Credit Facility, Remaining Borrowing Capacity Accounts Receivable Loans, Notes, Trade and Other Receivables Disclosure [Text Block] Contracts in Process Long-term Contracts or Programs Disclosure [Text Block] Long-term Debt, Current Maturities Current maturities of long-term debt Long-term Debt, Excluding Current Maturities Long-term debt, net of current maturities Loss Contingencies [Table] Balance at beginning of period Balance at end of period Loss Contingency Accrual, at Carrying Value Loss Contingency Nature [Axis] Net increases in reserves Loss Contingency Accrual, Carrying Value, Provision Roll forward of activity in the insurance reserves Loss Contingency Accrual [Roll Forward] Loss Contingencies [Line Items] Commitments and Contingencies Net payments made Loss Contingency Accrual, Carrying Value, Payments Contingent termination payment liability Loss Contingency, Estimate of Possible Loss Loss Contingency, Nature [Domain] Loss Contingency, Range of Possible Loss, Portion Not Accrued Estimated remaining cost to complete bonded projects Loss Contingency, Range of Possible Loss, Maximum Aggregate original face amount of outstanding bonds issued by the surety Major Customers [Axis] Advertising Marketing and Advertising Expense [Abstract] Maximum [Member] Maximum Minimum [Member] Minimum Percentage of total contribution to the plan Multiemployer Plans, Collective-Bargaining Arrangement, Percentage of Employer's Contributions Minimum future contributions (in dollars per hour) Multiemployer Plans, Minimum Contribution Multiemployer Plan Type [Axis] Multiemployer Plan Name [Axis] All other funds: Multiemployer Plan, Individually Insignificant Multiemployer Plans [Member] Multiemployer Plans Type [Domain] Multiemployer Plans [Abstract] Significant multiemployer plans Multiemployer Plan Name [Domain] Contributions to Plan Multiemployer Plans, Plan Contributions Minimum future contributions (as a percent) Multiemployer Plans, Collective-Bargaining Arrangement, Percentage of Contributions Multiemployer Plans [Line Items] Multiemployer pension plans Multiemployer pension plans Multiemployer Plans, Pension [Member] Name of Major Customer [Domain] Organization and Business Nature of Operations [Text Block] Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Cash flows from financing activities: Net cash flows provided by operating activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Cash flows from operating activities: Net increase (decrease) in cash and cash equivalents Net Cash Provided by (Used in) Continuing Operations Net Cash Provided by (Used in) Investing Activities, Continuing Operations Net cash flows used in investing activities Net Income (Loss) Available to Common Stockholders, Basic Net income available to common shareholders Net Income (Loss) Attributable to Parent [Abstract] Numerator: Net Cash Provided by (Used in) Financing Activities, Continuing Operations Net cash flows provided by (used in) financing activities Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Cash flows from investing activities: Net Income (Loss) Attributable to Parent Net income Net income Recently Issued and Adopted Accounting Pronouncements Noncash Investing and Financing Items [Abstract] Noncash investing activities: Acquisition of property and equipment through like-kind exchange of similar assets Noncash or Part Noncash Acquisition, Fixed Assets Acquired Nonoperating Income (Expense) [Abstract] Other income (expense): Number of Reportable Segments Number of business segments Number of reporting segments Office equipment Office Equipment [Member] Operating Leases, Future Minimum Payments, Due Thereafter Thereafter Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] Future minimum lease payments for operating leases Operating Leases, Future Minimum Payments, Remainder of Fiscal Year 2013 Operating Income (Loss) Income from operations Income from operations Operating Leases, Future Minimum Payments, Due in Three Years 2015 Operating Leases, Future Minimum Payments, Due in Two Years 2014 Operating Leases, Future Minimum Payments Due, Next Twelve Months 2013 Operating Leases, Future Minimum Payments, Due in Four Years 2016 Operating Leases, Future Minimum Payments, Due in Five Years 2017 Operating Leased Assets [Line Items] Leases Backlog Order or Production Backlog [Member] Organization, Business and Basis of Presentation Organization, Business and Basis of Presentation Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block] Other Receivables, Gross, Current Other Other Assets, Current Other current assets Other Assets, Noncurrent Other assets Other current liabilities Other Liabilities, Current [Abstract] Other Liabilities, Current Other current liabilities Other current liabilities, total Other Nonoperating Income (Expense) Other, net Other Liabilities, Noncurrent Other liabilities Other Noncash Expense Other non-cash items Other Other Accrued Liabilities, Current Other Employee Related Liabilities, Current Profit sharing and thrift plan Participating Securities, Distributed and Undistributed Earnings Less: Net income allocated to participating securities Accrued Liabilities Payments Related to Tax Withholding for Share-based Compensation Restricted stock tax withholdings Payments of Debt Issuance Costs Debt issuance costs Payments for Repurchase of Common Stock Purchase of treasury stock Equity financing costs Payments of Stock Issuance Costs Payments to Acquire Property, Plant, and Equipment Purchases of property and equipment Pension and Other Postretirement Benefits Disclosure [Text Block] Employee Benefit Plans Performance Shares [Member] Performance Awards Nonvested performance shares Plan Name [Domain] Plan Name [Axis] Preferred Stock, Shares Authorized Preferred stock, authorized shares Preferred Stock, Value, Outstanding Preferred stock-$0.01 par value per share; 4,000,000 authorized shares; none issued and outstanding at December 31, 2012 and 2011 Preferred Stock, Shares Issued Preferred stock, issued shares Preferred Stock, Par or Stated Value Per Share Preferred stock, par value (in dollars per share) Preferred Stock, Shares Outstanding Preferred stock, outstanding shares Preferred Stock Preferred Stock [Member] Reclassification Reclassification, Policy [Policy Text Block] Borrowings under revolving credit facility Proceeds from Issuance of Debt Other financing activities Proceeds from (Payments for) Other Financing Activities Net borrowings (repayments) on revolving credit facility Proceeds from (Repayments of) Lines of Credit Proceeds from Sale of Property, Plant, and Equipment Proceeds from sale of property and equipment Proceeds from Stock Options Exercised Employee stock option transactions Estimated useful lives Property, Plant and Equipment, Useful Life Estimated Useful Life Property, Plant and Equipment, Type [Domain] Property and Equipment Property and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Property, Plant and Equipment, Net Property and equipment, net of accumulated depreciation of $88,042 and $64,345, respectively Property and equipment, net Property and Equipment Property, Plant and Equipment [Line Items] Property, Plant and Equipment, Gross Property and equipment, gross Property, Plant and Equipment [Table Text Block] Schedule of property and equipment Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment Disclosure [Text Block] Property and Equipment Provision for Doubtful Accounts Reduction in (provision for) allowances Quarterly Financial Information [Text Block] Quarterly Financial Data (Unaudited) Quarterly Financial Data (Unaudited) Range [Axis] Range [Domain] Accounts Receivable Reconciliation of the beginning and ending liabilities for unrecognized tax benefits Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Reconciliation of Assets from Segment to Consolidated [Table] Schedule of identifiable assets for each segment Reconciliation of Assets from Segment to Consolidated [Table Text Block] Repayments of Long-term Debt Repayments on term loan Repayments of Long-term Capital Lease Obligations Payments of capital lease obligations Repayments under revolving credit facility Repayments of Long-term Lines of Credit Restricted Stock [Member] Restricted Stock Retained Earnings (Accumulated Deficit) Retained earnings Retained Earnings Retained Earnings [Member] Revenue Recognition Revenue Recognition [Abstract] Revenue Recognition Revenue Recognition, Policy [Policy Text Block] Revolving credit facility Revolving Credit Facility [Member] Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price Weighted-Average Exercise Price (in dollars per share) Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price Weighted-Average Exercise Price (in dollars per share) Exercisable at the end of the period (in dollars) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Expected term Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Exercisable at the end of the period Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Outstanding at the end of the period Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term Weighted-Average Remaining Contractual Term Revenues Sales [Member] Sales Revenue, Services, Net Contract revenues Revenues Scenario, Unspecified [Domain] Schedule of Multiemployer Plans [Table] Schedule of changes in outstanding shares of common stock Schedule of Common Stock Outstanding Roll Forward [Table Text Block] Schedule of income tax provision from continuing operations Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of the activity relating to the options outstanding under the Company's plans Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Schedule of Nonvested Performance-based Units Activity [Table Text Block] Schedule of performance stock award activity Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Schedule of supplemental disclosures of cash flow information Schedule of the assumptions used in determining the fair value of stock options granted for fixed awards with graded vesting schedules Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Schedule of goodwill and intangible assets Schedule of Intangible Assets and Goodwill [Table Text Block] Schedule of differences between the U.S. federal statutory tax rate and the Company's effective tax rate for continuing operations Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule of reconciliation of the beginning and ending liabilities for unrecognized tax benefits Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Schedule of restricted stock activity Schedule of Nonvested Restricted Stock Units Activity [Table Text Block] Schedule of Accrued Liabilities [Table Text Block] Schedule of other current liabilities Schedule of unaudited consolidated operating results by quarter Schedule of Quarterly Financial Information [Table Text Block] Schedule of net deferred tax assets and (liabilities) Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Multiemployer Plans [Table Text Block] Schedule of significant multiemployer plans Net income available to common shareholders and the weighted average number of common shares used to compute basic and diluted earnings per share Schedule of Calculation of Numerator and Denominator in Earnings Per Share [Table Text Block] Schedule of other data relating to option activity Schedule of Cash Proceeds Received from Share-based Payment Awards [Table Text Block] Schedule of Operating Leased Assets [Table] Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table] Schedule of information with respect to stock options outstanding and exercisable Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table Text Block] Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range [Table] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of internal financial reports used for corporate management purposes Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Property, Plant and Equipment [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Schedule of accounts receivable Segment Reporting, Asset Reconciling Item [Line Items] Identifiable assets, consisting of contract receivables, costs and estimated earnings in excess of billings on uncompleted contracts, construction materials inventory, goodwill and intangibles for each segment Segment Reporting Information [Line Items] Internal financial reports An allocation of total depreciation, including depreciation of shared construction equipment, and amortization Segment Information Segment Reporting Disclosure [Text Block] Segment Information Segment [Domain] Quarterly Financial Data (Unaudited) Selected Quarterly Financial Information [Abstract] Self Insurance Reserve, Current Accrued self insurance Selling, General and Administrative Expense Selling, general and administrative expenses Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Number of Shares Share-based Compensation Stock-based compensation expense Forfeited (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Outstanding at the beginning of the period (in dollars per share) Outstanding unvested at the end of the period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Exercised Shares earned by the participants Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward] Weighted-Average Grant Date Fair Value Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Additional disclosures Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Stock-Based Compensation Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Outstanding at the beginning of the period (in shares) Outstanding unvested at the end of the period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Vesting of performance shares Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Forfeited (in dollars per share) Granted (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Expired (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Granted (in shares) Exercised (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Risk-free interest rate (as a percent) Exercisable at the end of the period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Expected dividend yield (as a percent) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Weighted average expected volatility (as a percent) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Weighted Average Volatility Rate Expired (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Vested (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Weighted average grant-date fair value (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value Intrinsic value of options exercised (in dollars) Weighted Average Remaining Contractual Term Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Exercisable at the end of the period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Summary of the activity relating to the options outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Maximum grants of awards (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Assumptions used in determining the fair value of stock options granted for fixed awards with graded vesting schedules Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract] Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Exercisable Options Number Of Options (in shares) Exercise Price Range [Axis] Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items] Stock options outstanding Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Domain] Outstanding at the beginning of the period (in dollars per share) Outstanding at the end of the period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Outstanding at the end of the period (in dollars) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Number of Outstanding Options Number Of Options (in shares) Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit Exercise price, low end of range (in dollars per share) Outstanding at the beginning of the period (in shares) Outstanding at the end of the period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Award Type [Domain] Stock-Based Compensation Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit Exercise price, high end of range (in dollars per share) Share-based Goods and Nonemployee Services Transaction, Quantity of Securities Issued Stock issued to independent directors for annual retainer (in shares) Shares received as payment for withholding taxes due by holders of awards Shares Paid for Tax Withholding for Share Based Compensation Short-term Debt Short-term borrowings Outstanding amount of credit agreement Significant Accounting Policies [Text Block] Summary of Significant Accounting Policies Purchase Commitment, Remaining Minimum Amount Committed Outstanding purchase obligations for certain construction equipment Estimated reduction in unrecognized tax benefit due to the lapses in the applicable statutes of limitations and pending federal tax settlements Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit Statement [Table] Scenario [Axis] Statement Statement [Line Items] Stockholders' Equity CONSOLIDATED STATEMENTS OF STOCKHOLDERS EQUITY CONSOLIDATED STATEMENTS OF CASH FLOWS Business Segments [Axis] Equity Components [Axis] CONSOLIDATED BALANCE SHEETS Stock issuances Stock Issued or Granted During Period, Share-based Compensation [Abstract] Stock Options [Member] Assumed exercise of stock options Restricted stock grants (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Gross Restricted stock forfeitures (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Forfeited Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures New shares issued upon the exercise of vested stock options Stock repurchased Stock Repurchased During Period, Value Stock Option [Member] Stock Option Stock appreciation right Stock Appreciation Rights (SARs) [Member] Stock Issued During Period, Value, Issued for Noncash Considerations Fair value of stock issued to independent directors for annual retainer (in dollars) Stock issued under compensation plans, net Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures Forfeiture of restricted stock Stock Issued During Period, Value, Restricted Stock Award, Forfeitures Stock option exercises (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Exercised (in shares) Stock Issued During Period, Value, Other Stock issued - other Restricted stock activity (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Stockholders' Equity Attributable to Parent [Abstract] Stockholders' equity Stockholders' Equity Attributable to Parent Total stockholders' equity Balance Balance Stockholders' Equity. Stockholders' Equity Note Disclosure [Text Block] Stockholders' Equity Stockholders' Equity, Period Increase (Decrease) Subsequent Events [Text Block] Subsequent Events Subsequent Events Subsidiaries [Member] Subsidiary Supplemental Cash Flows Surety Bond [Member] Surety bonds Title of Individual with Relationship to Entity [Domain] Accounts Receivable and Allowance for Doubtful Accounts Trade and Other Accounts Receivable, Policy [Policy Text Block] Treasury Stock, Value Treasury stock, at cost - 3,310 and 0 shares, respectively Treasury Stock, Shares Treasury stock, shares Treasury Stock Treasury Stock [Member] Treasury Stock, Value, Acquired, Cost Method Return of shares in lieu of payroll tax withholding Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense Interest and penalties charged to income tax expense as a result of the unrecognized tax benefits Accrued interest and penalties at end of period Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Gross increases in current period tax positions Unrecognized Tax Benefits, Increases Resulting from Current Period Tax Positions Unrecognized Tax Benefits Balance at end of period Total unrecognized tax benefits Balance at beginning of period Lapse of applicable statutes of limitations Unrecognized Tax Benefits, Reductions Resulting from Lapse of Applicable Statute of Limitations Unrecognized Tax Benefits, Period Increase (Decrease) Additional amount recorded in unrecognized tax benefits related to the net activity of current year and prior year positions Settlements with taxing authorities Unrecognized Tax Benefits, Decreases Resulting from Settlements with Taxing Authorities Gross increases in prior period tax positions Unrecognized Tax Benefits, Increases Resulting from Prior Period Tax Positions Gross decreases in prior period tax positions Unrecognized Tax Benefits, Decreases Resulting from Prior Period Tax Positions Use of Estimates Use of Estimates, Policy [Policy Text Block] Taxes collected from customers Utility, Revenue and Expense Recognition, Policy [Policy Text Block] Weighted Average Number of Shares Outstanding, Basic [Abstract] Denominator: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Weighted average number of common shares and potential common shares outstanding: Weighted Average Number of Shares Outstanding, Basic -Basic (in shares) Weighted average common shares outstanding Weighted Average Number of Shares Outstanding, Diluted -Diluted (in shares) Weighted average common shares outstanding, diluted Weighted Average Number Diluted Shares Outstanding Adjustment Weighted average dilutive securities (in shares) Union dues and benefits Workers' Compensation Liability, Current Labour employees covered by collective bargaining agreements Workforce Subject to Collective Bargaining Arrangements [Member] Period for Settlement of Majority of Balances Under Construction Contract Maximum period for settlement of majority of balances under construction contract Represents the maximum period for settlement of majority of balances under construction contract. Number of Customers Individually Exceeding 10 Percent of Consolidated Contract Revenue Number of customers individually exceeding 10.0% of consolidated contract revenue Represents the number of customers individually exceeding 10 percent of consolidated contract revenue. Indefinite-Lived Trade Names Indefinite-lived intangible tradenames Accrued Payroll and Incentive Compensation, Current Payroll and incentive compensation Carrying value as of the balance sheet date of the obligations incurred through that date and payable for employees' services provided, including obligations incurred and payable for incentive compensation awarded to employees. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Accrued Union Dues and Benefits Union dues and benefits Carrying value as of the balance sheet date of the obligations incurred through that date and payable for union dues and benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Stock Repurchase Program, Authorized Amount Authorized amount of stock to be repurchased ShareBasedCompensationArrangementByShare Based Payment Award Percentage of Target Awards Earned Target awards earned during the performance period (as a percent) Represents the percentage of target awards earned for the performance period. Outstanding Performance Bonds Aggregate original face amount of outstanding bonds issued by the surety The total amount of outstanding performance bonds. Estimated Cost to Complete Bonded Projects Estimated remaining cost to complete bonded projects Estimated cost to complete bonded projects. Multiemployer Plan, Period Contributions Contributions to Plan Multiemployer Plans Minimum Contribution as Percent of Wages Minimum future contributions (as a percent) Amount of minimum contribution(s) as a percent of wages required for future periods to a multiemployer plan by collective bargaining arrangements, statutory obligations, or other contractual obligations. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.