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] 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 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. 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 Actual amount of RSUs earned based on cumulative earnings Share Based Compensation Arrangement By Share Based Payment Award Percent Of Actual Amount Of Units Earned Share based compensation arrangement by share based payment award percent of actual amount of units earned. Target RSUs granted range Share Based Compensation Arrangement By Share Based Payment Award Target R S U Granted Range Share based compensation arrangement by share based payment award target RSU granted range. Unvested restricted stock outstanding (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Compensation expense Allocated Share-based Compensation Expense Shares issued under the plan 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 granted (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Gross Statement of Cash Flows [Abstract] Operating Activities: Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Net loss Net Income (Loss) Attributable to Parent Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation Depreciation Amortization Amortization Stock-based compensation Share-based Compensation Bad debt recovery Provision for Doubtful Accounts 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 Costs and billings in excess of estimated earnings on uncompleted contracts Increase (Decrease) in Unbilled Receivables 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, Continuing Operations Investing Activities: Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Proceeds from sale of property, plant and equipment Proceeds from Sale of Property, Plant, and Equipment 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 Changes in restricted cash Increase in Restricted Cash Purchases of property, plant and equipment Payments to Acquire Property, Plant, and Equipment Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities, Continuing Operations 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, Continuing Operations Net increase (decrease) in cash and cash equivalents Cash and 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 and Cash Equivalents Cash and cash equivalents, beginning of period Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents, end of period Organization, Consolidation and Presentation of Financial Statements [Abstract] 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 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] 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 to 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 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 Fair Value Disclosures [Abstract] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value, Measurements, Recurring Fair Value, Measurements, Recurring [Member] Fair Value, Hierarchy Fair Value, Hierarchy [Axis] Fair Value Hierarchy Fair Value Hierarchy [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 Deferred compensation Deferred Compensation Plan Assets Fair Value Disclosure Deferred compensation plan assets fair value disclosure. Liabilities: Liabilities, Fair Value Disclosure [Abstract] Deferred compensation Deferred Compensation Liability, Current and Noncurrent Fair Value of Assets and Liabilities Measured on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] FAIR VALUE MEASUREMENTS Fair Value Disclosures [Text Block] INCOME TAXES Income Tax Disclosure [Text Block] DETAIL OF SELECTED BALANCE SHEET ACCOUNTS Supplemental Balance Sheet Disclosures [Text Block] Income Statement [Abstract] Revenues Contracts Revenue Cost of goods sold Contract Revenue Cost 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: Earnings Per Share [Abstract] Basic (in dollars per share) Earnings Per Share, Basic Diluted (in dollars per share) Earnings Per Share, Diluted Weighted average shares: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Dividends per share (in dollars per share) Common Stock, Dividends, Per Share, Declared EARNINGS PER SHARE Earnings Per Share [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] Allowance for doubtful accounts Allowance for Doubtful Accounts Receivable, Current 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 Debt Disclosure [Abstract] LONG-TERM DEBT Long-term Debt [Text Block] Numerator: Net Income (Loss) Attributable to Parent [Abstract] Denominator: Weighted average basic shares (in shares) Dilutive effect of restricted stock units (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Weighted average diluted shares with assumed conversions Net loss per share: Earnings Per Share, Basic and Diluted [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 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 Forfeited/cancelled (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited 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 Forfeited/canceled (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Outstanding at end of period(in dollars per share) Schedule of Effective Income Tax Rate Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Commitments and Contingencies Disclosure [Abstract] COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] ASSETS Assets [Abstract] Current Assets: Assets, Current [Abstract] Cash and cash equivalents Short-term investments Short-term Investments Restricted cash Restricted Cash and Cash Equivalents, Current Accounts receivable, less allowance for doubtful accounts of $158 and $179 Accounts Receivable, Net, Current Costs and estimated earnings in excess of billings on uncompleted contracts Costs in Excess of Billings, Current Inventories Income taxes receivable Income Taxes Receivable, Current Deferred income taxes Deferred Tax Assets, Net of Valuation Allowance, 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) Other assets Other Assets, Noncurrent Deferred income taxes Deferred Tax Assets, Net of Valuation Allowance, 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 salaries, bonuses and commissions Employee-related Liabilities, Current Billings in excess of costs and estimated earnings on uncompleted contracts Billings in Excess of Cost, Current Accrued product warranty Income taxes payable Accrued Income Taxes, Current Other accrued expenses Other Accrued Liabilities, Current Deferred credit ─ short term Deferred Revenue and Credits, 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 E) 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; 12,256,956 and 12,234,656 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 Stockholders' Equity Attributable to Parent Total Liabilities and Stockholders' Equity Liabilities and Equity Schedule of Restricted Stock Units Activity Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block] Components of Long-term debt Schedule of Long-term Debt Instruments [Table Text Block] Subsequent Events [Abstract] SUBSEQUENT EVENTS Subsequent Events [Text Block] Costs incurred on uncompleted contracts Costs Incurred On Uncompleted Contracts Costs incurred on uncompleted contracts. Estimated earnings Estimated Earnings Estimated earnings. Total Receivables, Long-term Contracts or Programs Less: Billings to date Billed Contracts Receivable Net underbilled position Unbilled Contracts Receivable Included in the accompanying balance sheets under the following captions: Contracts Receivable [Abstract] Costs and estimated earnings in excess of billings on uncompleted contracts Billings in excess of costs and estimated earnings on uncompleted contracts Allowance for Doubtful Accounts Receivable [Roll Forward] Allowance for Doubtful Accounts Receivable [Roll Forward] Balance at beginning of period Bad debt expense (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 Guarantee Obligations [Table] Schedule of Guarantor Obligations [Table] Credit Facility Credit Facility [Axis] Credit Facility Credit Facility [Domain] U.S. Revolver Domestic Line of Credit [Member] 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] Surety Bonds Surety Bond [Member] Debt Instrument Debt Instrument [Axis] Debt Instrument, Name Debt Instrument, Name [Domain] 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] Guarantee liability Guarantor Obligations, Current Carrying Value Additional bonding capacity Commitments And Contingencies Additional Bonding Capacity Commitments and contingencies additional bonding capacity. Revolving credit facility Line of Credit Facility, Maximum Borrowing Capacity Amount of credit facility remaining borrowing capacity Line of Credit Facility, Remaining Borrowing Capacity Liquidated damages Loss Contingency, Loss in Period Probable liquidated damages Loss Contingency Probable Loss In Period Loss contingency probable loss in period. Loss contingency, estimate of actual or projected loss Loss Contingency, Estimate of Possible Loss 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 Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Statement of Comprehensive Income [Abstract] Net loss 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 Line Of Credit Facility [Table] Line of Credit Facility [Table] Industrial Development Revenue Bonds Industrial Development Revenue Bonds [Member] Industrial development revenue bonds. 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 borrowings, outstanding amount Long-term Line of Credit 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 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 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) 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] Components of Cost and Estimated Earnings on Uncompleted Contracts Costs in Excess of Billings and Billings in Excess of Costs [Table Text Block] Activity in Product Warranty Accrual Schedule of Product Warranty Liability [Table Text Block] Income Tax Contingency [Table] Income Tax Contingency [Table] Tax Credit Carryforward [Axis] Tax Credit Carryforward [Axis] Tax Credit Carryforward, Name [Domain] Tax Credit Carryforward, Name [Domain] Research And Development Tax Credit Research And Development Tax Credit [Member] Research and development tax credit. Income Tax Contingency [Line Items] Income Tax Contingency [Line Items] Income tax benefit 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 Valuation allowance Operating Loss Carryforwards, Valuation Allowance Release of Fin 48 reserve relating to Research and Development Tax Credit Unrecognized Tax Benefits Computation of Basic and Diluted Earnings Per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] STOCK-BASED COMPENSATION Disclosure of Compensation Related Costs, Share-based Payments [Text Block]