Subsequent Events [Abstract] Subsequent Event [Table] Subsequent Event [Table] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] Subsequent Event [Line Items] Subsequent Event [Line Items] Quarterly cash dividend (in dollars per share) Common Stock, Dividends, Per Share, Declared Statement of Comprehensive Income [Abstract] Net loss Net Income (Loss) Attributable to Parent Foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Commitments and Contingencies Disclosure [Abstract] COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Income Tax Disclosure [Abstract] Loss before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Income tax benefit Income Tax Expense (Benefit) Net loss Effective tax rate Effective Income Tax Rate Reconciliation, Percent Organization, Consolidation and Presentation of Financial Statements [Abstract] Activity in Allowance for Doubtful Accounts Receivable Allowance for Credit Losses on Financing Receivables [Table Text Block] Components of Inventories Schedule of Inventory, Current [Table Text Block] Activity in Product Warranty Accrual Schedule of Product Warranty Liability [Table Text Block] Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type Award Type [Axis] Equity Award Equity Award [Domain] Restricted Stock Units (RSUs) Restricted Stock Units (RSUs) [Member] Restricted Stock Restricted Stock [Member] Class of Stock Class of Stock [Axis] Class of Stock Class of Stock [Domain] Time Based Restricted Stock Unit Time Based Restricted Stock Unit [Member] Time based restricted stock unit. Performance Based Restricted Stock Unit Performance Based Restricted Stock Unit [Member] Performance based restricted stock unit. Plan Name Plan Name [Axis] Plan Name Plan Name [Domain] Non Employee Director Equity Incentive Plan Non Employee Director Equity Incentive Plan [Member] 2014 Non-Employee Director Equity Incentive Plan Member Vesting Vesting [Axis] Vesting Vesting [Domain] Immediate Vesting Share-based Compensation Award, Tranche One [Member] Anniversary of Grant Date Share-based Compensation Award, Tranche Two [Member] Share Based Compensation Arrangement By Share Based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Unvested restricted stock outstanding (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Compensation expense (less than for restricted stock) Allocated Share-based Compensation Expense Shares issued under the plan (in shares) Share Based Compensation Arrangement By Share Based Payment Award Annual Shares Issuable Share-based compensation arrangement by share-based payment award annual shares issuable. Vesting, percentage Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Restricted stock issued (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock Common Stock [Member] Additional Paid-in Capital Additional Paid-in Capital [Member] Retained Earnings Retained Earnings [Member] Treasury Stock Treasury Stock [Member] Acummulated Other Comprehensive Income AOCI Attributable to Parent [Member] Statement [Line Items] Statement [Line Items] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Balance Stockholders' Equity Attributable to Parent Balance, shares Common Stock, Shares, Outstanding Net loss Foreign currency translation adjustments Stock-based compensation Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures Stock-based compensation, shares Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures Shares withheld in lieu of employee tax withholding Adjustments Related to Tax Withholding for Share-based Compensation Dividends paid Dividends, Common Stock, Cash Balance Balance, shares Earnings Per Share [Abstract] Numerator: Net Income (Loss) Attributable to Parent [Abstract] Denominator: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Weighted average basic shares (in shares) Weighted Average Number of Shares Outstanding, Basic Dilutive effect of restricted stock units (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Weighted average diluted shares Weighted Average Number of Shares Outstanding, Diluted Loss per share: Earnings Per Share, Basic and Diluted [Abstract] Basic (in dollars per share) Earnings Per Share, Basic Diluted (in dollars per share) Earnings Per Share, Diluted SUBSEQUENT EVENTS Subsequent Events [Text Block] DETAIL OF SELECTED BALANCE SHEET ACCOUNTS Supplemental Balance Sheet Disclosures [Text Block] Revenue from Contract with Customer [Abstract] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] United States UNITED STATES Canada CANADA Europe, Middle East and Africa EMEA [Member] Asia/Pacific Asia Pacific [Member] Mexico, Central and South America Mexico, Central America And South America [Member] Mexico, Central America And South America [Member] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] Oil and gas Oil and Gas Service [Member] Petrochemical 325110 Petrochemical Manufacturing [Member] Electric utility Electricity [Member] Traction power Traction Power Customer [Member] Traction Power Customer [Member] All others Other, Customers [Member] Other, Customers [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Revenues Revenue from Contract with Customer, Excluding Assessed Tax Statement of Cash Flows [Abstract] Operating Activities: Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Adjustments to reconcile net loss to net cash provided by (used in) operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Depreciation, Depletion and Amortization Stock-based compensation Share-based Compensation Bad debt expense (recovery) Provision for Doubtful Accounts Bad debt expense (recovery) Allowance for Doubtful Accounts Receivable, Recoveries Deferred income tax benefit Deferred Income Tax Expense (Benefit) Gain on amended supply agreement Gain (Loss) on Disposition of Intangible Assets Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable, net Increase (Decrease) in Accounts Receivable Contract assets and liabilities, net Increase (Decrease) In Contract With Customer Asset And Liability, Net Increase (Decrease) In Contract With Customer Asset And Liability, Net Inventories Increase (Decrease) in Inventories Income taxes Increase (Decrease) in Income Taxes Payable Prepaid expenses and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Accounts payable Increase (Decrease) in Accounts Payable Accrued liabilities Increase (Decrease) in Accrued Liabilities Other, net Increase (Decrease) in Other Operating Assets and Liabilities, Net Net cash provided by (used in) operating activities Net Cash Provided by (Used in) Operating Activities Investing Activities: Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Purchases of short-term investments Payments to Acquire Short-term Investments Maturities of short-term investments Proceeds from Maturities, Prepayments and Calls of Short-term Investments Purchases of property, plant and equipment Payments to Acquire Property, Plant, and Equipment Proceeds from sale of property, plant and equipment Proceeds from Sale of Property, Plant, and Equipment Net cash provided by investing activities Net Cash Provided by (Used in) Investing Activities Financing Activities: Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Payments on industrial development revenue bonds Repayments of Long-term Debt Shares withheld in lieu of employee tax withholding Payments Related to Tax Withholding for Share-based Compensation Dividends paid Payments of Ordinary Dividends, Common Stock Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities Net increase (decrease) in cash, cash equivalents and restricted cash Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect Effect of exchange rate changes on cash and cash equivalents Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash, cash equivalents and restricted cash, beginning of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash, cash equivalents and restricted cash, end of period Document And Entity Information [Abstract] Document and entity information. Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Document Type Document Type Document Period End Date Document Period End Date Amendment Flag Amendment Flag Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Trading Symbol Trading Symbol Entity Emerging Growth Company Entity Emerging Growth Company Entity Small Business Entity Small Business Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Accounting Policies [Abstract] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] New Accounting Standards New Accounting Pronouncements, Policy [Policy Text Block] Revenue Recognition Revenue from Contract with Customer [Policy Text Block] Raw materials, parts and subassemblies, net Inventory, Raw Materials and Supplies, Net of Reserves Work-in-progress Inventory, Work in Process, Gross Total inventories Inventory, Net Contract assets Contract with Customer, Asset, Net, Current Contract liabilities Contract with Customer, Liability, Current Net contract assets (liabilities) Contract With Customer, Asset (Liability), Net, Current Contract with Customer, Asset (Liability), Net, Current Revenue recognized related to contract liabilities Contract with Customer, Liability, Revenue Recognized Retention amounts included in accounts receivable Contract Receivable Retainage Retained amount expected to be collected in the next twelve months Contract Receivable Retainage, Next Twelve Months Revenue from products and services transferred to customers over time, percent Revenue Performance Obligation Satisfied Over Time, Percentage Revenue Performance Obligation Satisfied Over Time, Percentage Revenue from sales orders, percentage Revenue From Sales Orders, Percentage Revenue From Sales Orders, Percentage Changes in contract estimates related to projects in progress Contract with Customer, Asset, Cumulative Catch-up Adjustment to Revenue, Change in Measure of Progress RSU Activity (number of shares) [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Number of Restricted Stock Units Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Outstanding at beginning of period (in shares) Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Outstanding at end of period (in shares) Weighted Average Fair Value Per Share Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Outstanding at beginning of period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, 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, Grants in Period, Weighted Average Grant Date Fair Value Vested (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Outstanding at end of period (in dollars per share) Debt Disclosure [Abstract] Industrial development revenue bonds Long-term Debt Less current portion Long-term Debt and Capital Lease Obligations, Current Total long-term debt Long-term Debt and Capital Lease Obligations Fair Value Disclosures [Abstract] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, Hierarchy Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy Fair Value Hierarchy and NAV [Domain] Quoted Prices in Active Markets for Identical Assets (Level 1) Fair Value, Inputs, Level 1 [Member] Significant Other Observable Inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Significant Unobservable Inputs (Level 3) Fair Value, Inputs, Level 3 [Member] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Assets: Assets, Fair Value Disclosure [Abstract] Cash and cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Short-term investments Short-term Investments, Fair Value Disclosure Short-term Investments, Fair Value Disclosure Restricted cash Restricted Cash, Fair Value Disclosure Restricted Cash, Fair Value Disclosure Other assets Other Assets, Fair Value Disclosure Liabilities: Liabilities, Fair Value Disclosure [Abstract] Deferred compensation Deferred Compensation Liability, Current and Noncurrent Schedule of Calculation of the Effective Income Tax Rate Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Fair Value of Assets and Liabilities Measured on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Movement in Standard Product Warranty Accrual [Roll Forward] Movement in Standard Product Warranty Accrual [Roll Forward] Balance at beginning of period Product Warranty Accrual, Current Increase in warranty expense Standard and Extended Product Warranty Accrual, Increase for Warranties Issued Deduction for warranty charges Standard and Extended Product Warranty Accrual, Decrease for Payments Change due to foreign currency translation Standard and Extended Product Warranty Accrual, Foreign Currency Translation Gain (Loss) Balance at end of period Income Statement [Abstract] Cost of goods sold Cost of Goods and Services Sold Gross profit Gross Profit Selling, general and administrative expenses Selling, General and Administrative Expense Research and development expenses Research and Development Expense Amortization of intangible assets Amortization of Intangible Assets Operating loss Operating Income (Loss) Other income Other Nonoperating Income (Expense) Interest expense Interest Expense Interest income Investment Income, Interest Loss before income taxes Income tax benefit Loss per share: Weighted average shares: Basic (in shares) Diluted (in shares) Dividends per share (in dollars per share) EARNINGS PER SHARE Earnings Per Share [Text Block] FAIR VALUE MEASUREMENTS Fair Value Disclosures [Text Block] STOCK-BASED COMPENSATION Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Remaining performance obligation, amount Revenue, Remaining Performance Obligation, Amount Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Remaining performance obligation, expected timing of satisfaction, period Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Blended tax rate Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Re-measurement of deferred tax assets Deferred Tax Assets, Tax Deferred Expense, Other REVENUE Revenue from Contract with Customer [Text Block] LONG-TERM DEBT Long-term Debt [Text Block] OVERVIEW AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block] Statement of Financial Position [Abstract] ASSETS Assets [Abstract] Current Assets: Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Short-term investments Short-term Investments Restricted cash Restricted Cash and Cash Equivalents, Current Accounts receivable, less allowance for doubtful accounts of $139 and $157 Accounts Receivable, Net, Current Contract assets Inventories Income taxes receivable Income Taxes Receivable, Current Prepaid expenses Prepaid Expense, Current Other current assets Other Assets, Current Total Current Assets Assets, Current Property, plant and equipment, net Property, Plant and Equipment, Net Restricted cash Restricted Cash and Cash Equivalents, Noncurrent Goodwill and intangible assets, net Intangible Assets, Net (Including Goodwill) Deferred income taxes Deferred Tax Assets, Net of Valuation Allowance, Noncurrent Other assets Other Assets, Noncurrent Total Assets Assets LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity [Abstract] Current Liabilities: Liabilities, Current [Abstract] Current maturities of long-term debt Long-term Debt, Current Maturities Accounts payable Accounts Payable, Current Accrued compensation and benefits Employee-related Liabilities, Current Accrued product warranty Income taxes payable Accrued Income Taxes, Current Other current liabilities Other Accrued Liabilities, Current Total Current Liabilities Liabilities, Current Long-term debt, net of current maturities Long-term Debt, Excluding Current Maturities Deferred compensation Deferred Compensation Liability, Classified, Noncurrent Other long-term liabilities Other Liabilities, Noncurrent Total Liabilities Liabilities Commitments and Contingencies (Note F) Commitments and Contingencies Stockholders' Equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, par value $.01; 5,000,000 shares authorized; none issued Preferred Stock, Value, Issued Common stock, par value $.01; 30,000,000 shares authorized; 12,322,166 and 12,280,556 and shares issued, respectively Common Stock, Value, Outstanding Additional paid-in capital Additional Paid in Capital, Common Stock Retained earnings Retained Earnings (Accumulated Deficit) Treasury stock, 806,018 shares at cost Treasury Stock, Value Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Total Stockholders' Equity Total Liabilities and Stockholders' Equity Liabilities and Equity Line Of Credit Facility [Table] Line of Credit Facility [Table] Credit Facility Credit Facility [Axis] Credit Facility Credit Facility [Domain] U.S. Revolver Domestic Line of Credit [Member] Industrial Development Revenue Bonds Industrial Development Revenue Bonds [Member] Industrial development revenue bonds. Guarantor Obligations, Nature Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature Guarantor Obligations, Nature [Domain] Financial Standby Letter of Credit Financial Standby Letter of Credit [Member] Debt Instrument Debt Instrument [Axis] Debt Instrument, Name Debt Instrument, Name [Domain] The Third Amendment The Third Amendment [Member] The Third Amendment [Member] Variable Rate Variable Rate [Axis] Variable Rate Variable Rate [Domain] Federal Funds Rate Federal Funds Effective Swap Rate [Member] Eurocurrency Rate Eurodollar [Member] Range Range [Axis] Range Range [Domain] Maximum Maximum [Member] Line Of Credit Facility [Line Items] Line of Credit Facility [Line Items] Revolving credit facility Line of Credit Facility, Maximum Borrowing Capacity Guarantee liability Guarantor Obligations, Current Carrying Value Revolving credit facility borrowings, outstanding amount Long-term Line of Credit Ratio of indebtedness to consolidated earnings before interest, taxes, depreciation and amortization Ratio Of Indebtedness To Consolidated Earnings Before Interest, Taxes, Depreciation And Amortization Ratio Of Indebtedness To Consolidated Earnings Before Interest, Taxes Depreciation And Amortization Ratio of consolidated earnings before interest, taxes, depreciation and amortization, less income taxes, capital expenditures, principal debt payments and interest charges Ratio Of Consolidated Earnings Before Interest, Taxes, Depreciation And Amortization, Less Income Taxes, Capital Expenditures, Principal Debt Payments And Interest Charges Ratio Of Consolidated Earnings Before Interest, Taxes, Depreciation And Amortization, Less Income Taxes, Capital Expenditures, Principal Debt Payments and Interest Charges Cash collateral percent of outstanding debt (at least) Line Of Credit Facility, Covenant Terms, Cash Collateral, Percent Of Debt Outstanding Line Of Credit Facility, Covenant Terms, Cash Collateral, Percent Of Debt Outstanding Cash collateral pledged balance Line Of Credit Facility, Collateral Amount Line Of Credit Facility, Collateral Amount Amount available under the credit facility Line of Credit Facility, Remaining Borrowing Capacity Basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate Percentage of voting capital stock pledged as collateral Percentage Of Domestic Capital Stock Pledged As Collateral For Credit Facility Percentage of domestic capital stock pledged as collateral for credit facility. Non-domestic subsidiaries of voting capital stock Percentage Of Non Domestic Capital Stock Pledged As Collateral For Credit Facility Percentage of non domestic capital stock pledged as collateral for credit facility. Borrowings Debt Instrument, Face Amount Reimbursement agreement requires annual redemptions Debt Instrument, Annual Principal Payment Interest rate Debt Instrument, Interest Rate, Effective Percentage Allowance for Doubtful Accounts Receivable [Roll Forward] Allowance for Doubtful Accounts Receivable [Roll Forward] Balance at beginning of period Allowance for Doubtful Accounts Receivable, Current Bad debt expense Bad debt (recovery) Uncollectible accounts written off, net of recoveries Allowance For Doubtful Accounts Receivable Write Offs Recoveries Allowance for doubtful accounts receivable write offs (recoveries). Change due to foreign currency translation Increase (Decrease) Due To Foreign Currency Translation Increase (decrease) due to foreign currency translation. Balance at end of period Schedule of Restricted Stock Units Activity Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block] Allowance for doubtful accounts Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Preferred stock, shares authorized Preferred Stock, Shares Authorized Preferred stock, shares issued Preferred Stock, Shares Issued Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, shares authorized Common Stock, Shares Authorized Common stock, shares issued Common Stock, Shares, Issued Treasury stock, shares Treasury Stock, Shares Components of Long-term debt Schedule of Long-term Debt Instruments [Table Text Block] Schedule Of Guarantee Obligations [Table] Schedule of Guarantor Obligations [Table] Surety Bonds Surety Bond [Member] Facility Agreement Facility Agreement [Member] Facility agreement. Legal Entity Legal Entity [Axis] Entity Entity [Domain] Powell (UK) Limited Powell U K Limited [Member] Powell (UK) limited. Guarantee Obligations [Line Items] Guarantor Obligations [Line Items] Additional bonding capacity Commitments And Contingencies Additional Bonding Capacity Commitments and contingencies additional bonding capacity. Amount of credit facility remaining borrowing capacity Summary of Contract Asset and Liabilities Contract with Customer, Asset and Liability [Table Text Block] Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] INCOME TAXES Income Tax Disclosure [Text Block] Reconciliation of Basic and Diluted Weighted Average Shares used in Computation of Earnings Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]