Commitments and Contingencies Disclosure [Abstract] Cash settlement inclusive of fees and expenses Litigation Settlement, Amount Number of plaintiffs Loss Contingency, Number of Plaintiffs Number of claims Loss Contingency, Pending Claims, Number Organization, Consolidation and Presentation of Financial Statements [Abstract] Significant Accounting Policies and Supplemental Balance Sheet Information Significant Accounting Policies and Supplemental Balance Sheet Information [Text Block] The entire disclosure for all significant accounting policies of the reporting entity and for supplemental balance sheet disclosures, including descriptions and amounts for assets, liabilities, and equity. Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Statement, Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock Common Stock [Member] Treasury Stock Treasury Stock [Member] Additional Paid-In Capital Additional Paid-in Capital [Member] Accumulated Deficit Retained Earnings [Member] Other Accumulated Comprehensive Income (Loss) 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 (in shares) Shares, Outstanding Release of Restricted Stock Stock Issued During Period, Value, Restricted Stock Award, Gross Release of Restricted Stock (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Gross Shares held in treasury Adjustments Related to Tax Withholding for Share-based Compensation Shares held in treasury (in shares) Shares Paid for Tax Withholding for Share Based Compensation Net translation loss on foreign subsidiaries Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Stock-based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Net loss Net Income (Loss) Attributable to Parent Balance Balance (in shares) Statement of Financial Position [Abstract] ASSETS Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Restricted cash Restricted Cash and Cash Equivalents, Current Accounts receivable, net of allowance for doubtful accounts of $109 and $212 at September 30, 2015 and December 31, 2014, respectively Accounts Receivable, Net, Current Inventories, net Inventory, Net Prepaid expenses and other Prepaid Expense and Other Assets, Current Total current assets Assets, Current Property and equipment, net Property, Plant and Equipment, Net Deposits and other Other Assets, Noncurrent Total assets Assets LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Accrued expenses Accrued Liabilities, Current Deferred revenue Deferred Revenue, Current Revolving line of credit Line of Credit, Current Total current liabilities Liabilities, Current Long-term liabilities Other Liabilities, Noncurrent Commitments and contingencies Commitments and Contingencies Stockholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock - $0.001 par value; 2,000 shares authorized Preferred Stock, Value, Issued Common stock - $0.001 par value; 40,000 shares authorized; 23,169 and 23,162 shares issued and 23,108 and 23,094 shares outstanding at September 30, 2015 and December 31, 2014, respectively Common Stock, Value, Issued Treasury stock Treasury Stock, Value Additional paid-in capital Additional Paid in Capital, Common Stock Accumulated deficit Retained Earnings (Accumulated Deficit) Other accumulated comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Total stockholders' equity Total liabilities and stockholders' equity Liabilities and Equity ASSETS Current assets: Accounts receivable, allowance for doubtful accounts Allowance for Doubtful Accounts Receivable, Current Stockholders' equity: Preferred Stock, par value (in usd per share) Preferred Stock, Par or Stated Value Per Share Preferred Stock, shares authorized Preferred Stock, Shares Authorized Common Stock, par value (in usd 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 Common Stock, shares outstanding Common Stock, Shares, Outstanding Earnings Per Share [Abstract] Net loss Basic and dilutive: Earnings Per Share, Basic and Diluted [Abstract] Weighted-average shares of common stock outstanding used in computing basic and diluted net loss per share (in shares) Weighted Average Number of Shares Outstanding, Basic Basic and diluted net loss per share (usd per share) Earnings Per Share, Basic and Diluted Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Stock Options Employee Stock Option [Member] Restricted Stock Units (RSUs) Restricted Stock [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Common stock equivalents excluded from calculation because effect would have been anti-dilutive (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Net Loss Per Share Earnings Per Share [Text Block] Schedule of Guarantor Obligations [Table] Schedule of Guarantor Obligations [Table] Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Domain] Guarantor Obligations, Nature [Domain] Performance Guarantee Performance Guarantee [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Expires June 2017 Letter Of Credit Expiring on June 2017 [Member] Letter Of Credit Expiring on June 2017 [Member] Expired July 2015 Letter Of Credit Expiring on July 2015 [Member] Letter Of Credit Expiring on July 2015 [Member] Guarantor Obligations [Line Items] Guarantor Obligations [Line Items] Restricted Cash Restricted Cash and Investments [Abstract] Deposit guarantees outstanding for building lease Deposit guarantees outstanding for building lease Refers to the deposit amount outstanding for building lease. Performance guarantee outstanding deposit for building lease Performance guarantee outstanding deposit for fixed asset Performance guarantee outstanding deposit for fixed asset included in restricted cash. Receivables Receivables [Abstract] Trade receivables Accounts Receivable, Gross, Current Less: Allowance for doubtful accounts Accounts receivable, net Standard payment term Threshold Period Past Due for Write-off of Trade Accounts Receivable Extended payment term Threshold Period Past Due For Write-Off of Trade Accounts Receivable, Extended Term Threshold Period Past Due For Write-Off of Trade Accounts Receivable, Extended Term Inventory Inventory, Net [Abstract] Raw materials Inventory, Raw Materials, Net of Reserves Work in process Inventory, Work in Process, Net of Reserves Finished goods Inventory, Finished Goods, Net of Reserves Inventories, net Accrued Expenses Accounts Payable and Accrued Liabilities, Current [Abstract] Compensation, severance and benefits Employee-related Liabilities, Current Warranty liability included in Accrued expenses Product Warranty Accrual, Current Taxes, other than income Taxes Payable, Current Professional fees Accrued Professional Fees, Current Other Other Accrued Liabilities, Current Accrued expenses Warranty Liability Warranty Liability [Abstract] Standard power quality products warranty period from date of commissioning Standard power quality products warranty period from date of commissioning The standard power quality products warranty period from date of commissioning. Standard power quality products warranty period from date of shipment Standard power quality products warranty period from date of shipment The standard power quality products warranty period from date of shipment. Standard products warranty period for primary OEM customer Standard products warranty period for primary OEM customer The standard products warranty period from date of shipment to end user for primary OEM customer. Extended products warranty period from date of shipment to primary OEM customer, Maximum Extended products warranty period from date of shipment to primary OEM customer, Maximum The extended maximum products warranty period from date of shipment to primary OEM customer. Changes in warranty liability Movement in Standard Product Warranty Accrual [Roll Forward] Balance at December 31, 2014 Standard Product Warranty Accrual Warranty expense Standard Product Warranty Accrual, Warranties Issued Payments Standard Product Warranty Accrual, Payments Balance at September 30, 2015 Warranty liability included in Long-term liabilities Product Warranty Accrual, Noncurrent Balance at September 30, 2015 Revenue Recognition Revenue Recognition [Abstract] Number of criteria to be met for revenue recognition Number of criteria to be met for revenue recognition The number of criteria that must be met for the company to recognize revenue. Minimum number of CleanSource UPS or PowerHouse products included in significant MEAs Minimum number of first tier products included in significant MEAs The minimum number of products included in the entity's most significant MEAs related to first tier products. Minimum number of second tier products included in significant MEAs Minimum number of second tier products included in significant MEAs The minimum number of products included in the entity's most significant multiple element arrangements (MEAs) related to second tier products. Second tier products include design services, project management, commissioning and installation services, spare parts or consumables, and extended maintenance agreements. Commissioning and installation period Commissioning and installation period Under a multiple element arrangement, the typical period subsequent to product delivery during which commissioning and installation takes place. EMAs, consumables, repair, maintenance and consulting services general deliverable period, minimum EMAs, consumables, repair, maintenance and consulting services general deliverable period, minimum Under a multiple element arrangement, the minimum period over which extended maintenance agreements (EMAs), consumables, and repair and maintenance or consulting services generally are delivered. EMAs, consumables, repair, maintenance and consulting services general deliverable period, maximum EMAs, consumables, repair, maintenance and consulting services general deliverable period, maximum Under a multiple element arrangement, the maximum period over which extended maintenance agreements (EMAs), consumables, and repair and maintenance or consulting services generally are delivered. Debt Disclosure [Abstract] Revolving Line of Credit Debt Disclosure [Text Block] Document and Entity Information [Abstract] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Filer Category Entity Filer Category Document Type Document Type Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Guarantees [Abstract] Performance guarantee outstanding deposit for fixed asset Performance guarantees outstanding to customers Guarantor Obligations, Current Carrying Value Line of Credit Facility [Table] Line of Credit Facility [Table] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] U.K. and Germany U.K. And Germany [Member] U.K. And Germany [Member] Lender Name [Axis] Lender Name [Axis] Line of Credit Facility, Lender [Domain] Line of Credit Facility, Lender [Domain] Silicon Valley Bank Silicon Valley Bank [Member] Silicon Valley Bank [Member] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Revolving Line of Credit Revolving Credit Facility [Member] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] Prime Rate Prime Rate [Member] Line of Credit Facility Inventory Borrowing Rates [Line Items] Line of Credit Facility [Line Items] Line of Credit Facility [Abstract] Line of Credit Facility [Abstract] Extension of loan facility term Debt Instrument, Term Percentage of borrowing capacity Line of credit facility maximum borrowing capacity percentage Percentage for line of credit facility maximum borrowing capacity. Maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Current borrowing capacity Line of Credit Facility, Current Borrowing Capacity Inventory and purchase order availability Borrowing Base Sublimits Inventory and Purchase Orders Maximum borrowing limit under the credit facility agreement related to eligible inventory and purchase orders. Purchase orders and eligible inventory sublimit Purchase orders and eligible inventory amount subject to a sublimit Purchase orders and eligible inventory amount subject to a sublimit. Accounts receivable sublimit Borrowing Base Sublimits, Accounts Receivable Borrowing Base Sublimits, Accounts Receivable Liquidity Ratio for immediate reconciliation period Liquidity Ratio for reconciliation period Liquidity Ratio for immediate reconciliation period. Minimum prime rate Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum Basis spread on prime rate Debt Instrument, Basis Spread on Variable Rate End of period prime rate Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate Outstanding loan facility borrowings Line of Credit Facility, Average Outstanding Amount Additional borrowing base Line of Credit Facility, Remaining Borrowing Capacity Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Restricted Cash Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] Receivables Receivables, Policy [Policy Text Block] Inventories, net Inventory, Policy [Policy Text Block] Warranty Liability Standard Product Warranty, Policy [Policy Text Block] Revenue Recognition Revenue Recognition, Policy [Policy Text Block] Recently issued accounting pronouncements not yet adopted New Accounting Pronouncements, Policy [Policy Text Block] Computation of basic and diluted net loss per share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Guarantees Guarantees [Text Block] Fair Value Disclosures [Abstract] Fair Value of Financial Instruments Fair Value Disclosures [Text Block] Statement of Cash Flows [Abstract] Operating activities Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net loss to cash used in operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation expense Depreciation Net change to allowance for doubtful accounts Allowance for Doubtful Accounts Receivable, Period Increase (Decrease) Loss (gain) on disposal of fixed assets Gain (Loss) on Disposition of Property Plant Equipment Impairment on fixed assets Asset Impairment Charges Stock-based compensation Share-based Compensation Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Restricted cash Increase (Decrease) in Restricted Cash for Operating Activities Accounts receivable Increase (Decrease) in Accounts Receivable Inventories Increase (Decrease) in Inventories Prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Accounts payable Increase (Decrease) in Accounts Payable Accrued expenses Increase (Decrease) in Accrued Liabilities Deferred revenue Increase (Decrease) in Deferred Revenue Long term liabilities Increase (Decrease) in Other Noncurrent Liabilities Net cash used in operating activities Net Cash Provided by (Used in) Operating Activities Investing activities Net Cash Provided by (Used in) Investing Activities [Abstract] Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Proceeds from sale of fixed assets Proceeds from Sale of Property, Plant, and Equipment Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Financing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from public offering of common stock, net of issuance costs Proceeds from Issuance of Common Stock Proceeds from employee stock option exercises Proceeds from Stock Options Exercised Taxes paid related to net share settlement of equity awards Payments For Taxes Related To Settlement of Equity Awards The cash outflow associated with the payment of taxes related to the settlement of equity awards. Net cash (used in) provided by financing activities Net Cash Provided by (Used in) Financing Activities Effects of exchange rates on cash Effect of Exchange Rate on Cash and Cash Equivalents Change in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Basis of Presentation Business Description and Basis of Presentation [Text Block] Income Statement [Abstract] Revenues: Revenue, Net [Abstract] Product revenue Sales Revenue, Goods, Net Service and other revenue Sales Revenue, Services, Net Total revenue Revenue, Net Cost of goods sold: Cost of Goods and Services Sold [Abstract] Cost of product revenue Cost of Goods Sold Cost of service and other revenue Cost of Services Total cost of goods sold Cost of Goods and Services Sold Gross profit Gross Profit Operating expenses: Operating Expenses [Abstract] Research and development Research and Development Expense Selling and marketing Selling and Marketing Expense General and administrative General and Administrative Expense Total operating expenses Operating Expenses Loss from operations Operating Income (Loss) Interest expense, net Interest Income (Expense), Nonoperating, Net Other expense, net Nonoperating Income (Expense) Loss before income taxes Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest Income tax expense Income Tax Expense (Benefit) Net loss Net loss per share, basic and diluted (usd per share) Shares used in computing net loss per share, basic and diluted (in shares) Weighted Average Number of Shares Outstanding, Basic and Diluted Comprehensive loss: Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Translation loss on subsidiaries denominated in foreign currencies Translation Adjustment Functional to Reporting Currency, Loss (Gain), Reclassified to Earnings, Net of Tax Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Money-market funds for which the fair value was determined Restricted Cash and Cash Equivalents Accounts receivables Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block] Schedule of inventory Schedule of Inventory, Current [Table Text Block] Accrued Expenses Schedule of Accrued Liabilities [Table Text Block] Changes in warranty liability Schedule of Product Warranty Liability [Table Text Block]