Description of Business and Basis of Presentation (Policies)	6 Months Ended
Jun. 30, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Financial Statement Presentation	Financial Statement Presentation The accompanying condensed consolidated financial statements include the accounts of Maxwell Technologies, Inc. and its subsidiaries and have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”). All intercompany transactions and account balances have been eliminated in consolidation. The Company has prepared the accompanying unaudited interim condensed consolidated financial statements in accordance with the instructions to Form 10-Q and the standards of accounting measurement set forth in the Interim Reporting Topic of the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”). Consequently, the Company has not necessarily included in this Form 10-Q all information and footnotes required for audited financial statements. In the opinion of the Company’s management, the accompanying unaudited condensed consolidated financial statements in this Form 10-Q contain all adjustments (consisting only of normal recurring adjustments, except as otherwise indicated) necessary to present fairly the financial position, results of operations, and cash flows of Maxwell Technologies, Inc. for all periods presented. The results reported in these condensed consolidated financial statements should not be regarded as necessarily indicative of results that may be expected for any subsequent period or for the entire year. These unaudited condensed consolidated financial statements and notes thereto should be read in conjunction with the Company’s audited financial statements and the notes thereto included in the Company’s latest Annual Report on Form 10-K. Certain information and footnote disclosures normally included in the annual financial statements prepared in accordance with U.S. GAAP have been condensed or omitted in the accompanying interim consolidated financial statements. The year-end condensed balance sheet data was derived from audited financial statements, but does not include all disclosures required by U.S. GAAP.
Reclassifications	Reclassifications Foreign currency exchange gains and losses have been reclassified from "cost of revenue" and "selling, general and administrative" expenses to "foreign currency exchange losses, net" in the condensed consolidated statement of operations for the three and six months ended June 30, 2014 to conform to the current period presentation. These reclassifications do not impact reported net income (loss) and do not otherwise have a material impact on the presentation of the overall financial statements.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect reported amounts and related disclosures. These estimates include, but are not limited to, assessing the collectability of accounts receivable, applied and unapplied production costs, production capacities, the usage and recoverability of inventories and long-lived assets, including deferred income taxes, the incurrence of warranty obligations, impairment of goodwill and other intangible assets, estimation of the cost to complete certain projects, accruals for estimated losses from legal matters, and estimation of the value of stock-based compensation awards, including the probability that the performance criteria of restricted stock awards will be met.
Income Taxes	Income Taxes At June 30, 2015, the Company has a cumulative valuation allowance recorded offsetting its worldwide net deferred tax assets of $64.2 million, of which the significant majority represents the valuation allowance on its U.S. net deferred tax asset. The Company has established a valuation allowance against its U.S. federal and state deferred tax assets due to the uncertainty surrounding the realization of such assets. Management periodically evaluates the recoverability of the deferred tax assets and at such time as it is determined that it is more likely than not that U.S. deferred tax assets are realizable, the valuation allowance will be reduced accordingly. Any such release would result in recording a tax benefit that would increase net income in the period the valuation is released. The Company records taxes on the undistributed earnings of foreign subsidiaries unless the subsidiaries’ earnings are considered indefinitely reinvested outside of the U.S. As a result of changes in business circumstances, the Company changed its estimate of the amount of foreign subsidiary earnings considered permanently reinvested, and recorded a deferred tax liability in 2014 for Swiss withholding taxes of $1.6 million associated with $31.8 million of undistributed earnings of our Swiss subsidiary that were no longer considered indefinitely reinvested. In June 2015, based on revisions to the Company's long term plans, the Company again changed its estimate of the amount of foreign earnings considered permanently reinvested. Therefore, in the quarter ended June 30, 2015, the Company recorded an additional deferred tax liability for Swiss withholding taxes of $2.1 million associated with an additional $41.7 million of undistributed earnings of our Swiss subsidiary that are no longer considered indefinitely reinvested. In the event that the Company repatriates these funds, these withholding taxes would become payable.
Warranty Obligation	Warranty Obligation The Company provides warranties on all product sales for terms ranging from one to eight years. The Company accrues for the estimated warranty costs at the time of sale based on historical warranty experience plus any known or expected changes in warranty exposure.
Revenue Recognition	Revenue Recognition Revenue is derived primarily from the sale of manufactured products directly to customers. Product revenue is recognized, according to the guidelines of the Securities and Exchange Commission (“SEC”) Staff Accounting Bulletin (“SAB”) Numbers 101, Revenue Recognition in Financial Statements, and 104, Revenue Recognition, when all of the following criteria are met: (1) persuasive evidence of an arrangement exists (upon contract signing or receipt of an authorized purchase order from a customer); (2) title passes to the customer at either shipment from the Company’s facilities or receipt at the customer facility, depending on shipping terms; (3) customer payment is deemed fixed or determinable and free of contingencies or significant uncertainties; and (4) collectability is reasonably assured. This policy has been consistently applied from period to period. Revenue is not recognized for sales that do not meet the revenue recognition criteria at the time of sale. Revenue is recognized once all of the criteria for revenue recognition are determined to have been met. For example, if the Company does not believe that collection of the sales price is reasonably assured at the time of sale, it defers revenue recognition until cash is received. If the Company receives cash payment from the customer prior to the achievement of the revenue recognition criteria, the amount received from the customer is recorded as deferred revenue in the consolidated balance sheets. Total deferred revenue and customer deposits in the consolidated balance sheets as of June 30, 2015 and December 31, 2014 was $878,000 and $703,000, respectively, and relates to cash received from customers on sales for which the revenue recognition criteria had not been achieved, customer advances, as well as other less significant customer arrangements requiring the deferral of revenue.
Liquidity	Liquidity As of June 30, 2015, the Company had approximately $25.0 million in cash and cash equivalents, and working capital of $64.9 million. The Company has a total of $5.9 million in debt outstanding to its previous lender as of June 30, 2015, which was paid in full on July 3, 2015. In July 2015, the Company entered into a loan agreement with East West Bank (“EWB”), whereby EWB made available to the Company a secured credit facility in the form of a revolving line of credit which is available up to a maximum of the lesser of: (a) $25.0 million; or (b) a certain percentage of domestic and foreign trade receivables. Management believes the available cash balance, along with the available borrowings under the revolving line of credit, will be sufficient to fund its operations, obligations as they become due, and capital investments for at least the next twelve months.
Net Loss per Share	Net Loss per Share In accordance with the Earnings Per Share Topic of the FASB ASC, basic net income (loss) per share is calculated using the weighted average number of common shares outstanding during the period. Diluted net income per share includes the impact of additional common shares that would have been outstanding if potentially dilutive common shares were issued. Potentially dilutive securities are not considered in the calculation of diluted net loss per share, as their inclusion would be anti-dilutive.
Restructuring and Exit Costs	Restructuring and Exit Costs Restructuring and exit costs involve employee-related termination costs, facility exit costs and other costs associated with our restructuring activities. The Company accounts for charges resulting from operational restructuring actions in accordance with ASC Topic 420, Exit or Disposal Cost Obligations (“ASC 420”) and ASC Topic 712, Compensation-Nonretirement Postemployment Benefits (“ASC 712”). The recognition of restructuring costs require that the Company make certain assumptions related to the amounts of employee severance benefits, the time period over which leased facilities will remain vacant, expected sublease terms and discount rates. Estimates and assumptions are based on the best information available at the time the obligation arises. These estimates are reviewed and revised as facts and circumstances dictate; changes in these estimates could have a material effect on the amount accrued in the consolidated balance sheet.
Fair Value Measurements and Disclosures	The Company records certain financial instruments at fair value in accordance with the Fair Value Measurements and Disclosures Topic of the FASB ASC. As of June 30, 2015, the financial instruments to which this topic applied were foreign currency forward contracts. As of June 30, 2015, the fair value of these foreign currency forward contracts was a liability of $167,000 which is recorded in “accounts payable and accrued liabilities" in the consolidated balance sheet. The fair value of these derivative instruments is measured using models following quoted market prices in active markets for identical instruments, which is a Level 2 input under the fair value hierarchy of the Fair Value Measurements and Disclosures Topic of the FASB ASC.
Derivatives and Hedging	Maxwell uses forward contracts to hedge certain monetary assets and liabilities, primarily receivables and payables, denominated in foreign currencies. The change in fair value of these forward contracts represents a natural hedge as gains and losses on these instruments partially offset the changes in the fair value of the underlying monetary assets and liabilities due to movements in currency exchange rates. These forward contracts generally expire in one month. These contracts are considered economic hedges but are not designated as hedges under the Derivatives and Hedging Topic of the FASB ASC, therefore, the change in the fair value of the instrument is recognized each period in the consolidated statement of operations.

Description of Business and Basis of Presentation (Policies)

6 Months Ended

Jun. 30, 2015

Organization, Consolidation and Presentation of Financial Statements [Abstract]

The accompanying condensed consolidated financial statements include the accounts of Maxwell Technologies, Inc. and its subsidiaries and have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”). All intercompany transactions and account balances have been eliminated in consolidation. The Company has prepared the accompanying unaudited interim condensed consolidated financial statements in accordance with the instructions to Form 10-Q and the standards of accounting measurement set forth in the Interim Reporting Topic of the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”). Consequently, the Company has not necessarily included in this Form 10-Q all information and footnotes required for audited financial statements. In the opinion of the Company’s management, the accompanying unaudited condensed consolidated financial statements in this Form 10-Q contain all adjustments (consisting only of normal recurring adjustments, except as otherwise indicated) necessary to present fairly the financial position, results of operations, and cash flows of Maxwell Technologies, Inc. for all periods presented. The results reported in these condensed consolidated financial statements should not be regarded as necessarily indicative of results that may be expected for any subsequent period or for the entire year. These unaudited condensed consolidated financial statements and notes thereto should be read in conjunction with the Company’s audited financial statements and the notes thereto included in the Company’s latest Annual Report on Form 10-K. Certain information and footnote disclosures normally included in the annual financial statements prepared in accordance with U.S. GAAP have been condensed or omitted in the accompanying interim consolidated financial statements. The year-end condensed balance sheet data was derived from audited financial statements, but does not include all disclosures required by U.S. GAAP.

Reclassifications

Foreign currency exchange gains and losses have been reclassified from "cost of revenue" and "selling, general and administrative" expenses to "foreign currency exchange losses, net" in the condensed consolidated statement of operations for the three and six months ended June 30, 2014 to conform to the current period presentation. These reclassifications do not impact reported net income (loss) and do not otherwise have a material impact on the presentation of the overall financial statements.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect reported amounts and related disclosures. These estimates include, but are not limited to, assessing the collectability of accounts receivable, applied and unapplied production costs, production capacities, the usage and recoverability of inventories and long-lived assets, including deferred income taxes, the incurrence of warranty obligations, impairment of goodwill and other intangible assets, estimation of the cost to complete certain projects, accruals for estimated losses from legal matters, and estimation of the value of stock-based compensation awards, including the probability that the performance criteria of restricted stock awards will be met.

Income Taxes

At June 30, 2015, the Company has a cumulative valuation allowance recorded offsetting its worldwide net deferred tax assets of $64.2 million, of which the significant majority represents the valuation allowance on its U.S. net deferred tax asset. The Company has established a valuation allowance against its U.S. federal and state deferred tax assets due to the uncertainty surrounding the realization of such assets. Management periodically evaluates the recoverability of the deferred tax assets and at such time as it is determined that it is more likely than not that U.S. deferred tax assets are realizable, the valuation allowance will be reduced accordingly. Any such release would result in recording a tax benefit that would increase net income in the period the valuation is released.

The Company records taxes on the undistributed earnings of foreign subsidiaries unless the subsidiaries’ earnings are considered indefinitely reinvested outside of the U.S. As a result of changes in business circumstances, the Company changed its estimate of the amount of foreign subsidiary earnings considered permanently reinvested, and recorded a deferred tax liability in 2014 for Swiss withholding taxes of $1.6 million associated with $31.8 million of undistributed earnings of our Swiss subsidiary that were no longer considered indefinitely reinvested. In June 2015, based on revisions to the Company's long term plans, the Company again changed its estimate of the amount of foreign earnings considered permanently reinvested. Therefore, in the quarter ended June 30, 2015, the Company recorded an additional deferred tax liability for Swiss withholding taxes of $2.1 million associated with an additional $41.7 million of undistributed earnings of our Swiss subsidiary that are no longer considered indefinitely reinvested. In the event that the Company repatriates these funds, these withholding taxes would become payable.

Warranty Obligation

The Company provides warranties on all product sales for terms ranging from one to eight years. The Company accrues for the estimated warranty costs at the time of sale based on historical warranty experience plus any known or expected changes in warranty exposure.

Revenue Recognition

Revenue is derived primarily from the sale of manufactured products directly to customers. Product revenue is recognized, according to the guidelines of the Securities and Exchange Commission (“SEC”) Staff Accounting Bulletin (“SAB”) Numbers 101, Revenue Recognition in Financial Statements, and 104, Revenue Recognition, when all of the following criteria are met: (1) persuasive evidence of an arrangement exists (upon contract signing or receipt of an authorized purchase order from a customer); (2) title passes to the customer at either shipment from the Company’s facilities or receipt at the customer facility, depending on shipping terms; (3) customer payment is deemed fixed or determinable and free of contingencies or significant uncertainties; and (4) collectability is reasonably assured. This policy has been consistently applied from period to period.

Revenue is not recognized for sales that do not meet the revenue recognition criteria at the time of sale. Revenue is recognized once all of the criteria for revenue recognition are determined to have been met. For example, if the Company does not believe that collection of the sales price is reasonably assured at the time of sale, it defers revenue recognition until cash is received.

If the Company receives cash payment from the customer prior to the achievement of the revenue recognition criteria, the amount received from the customer is recorded as deferred revenue in the consolidated balance sheets. Total deferred revenue and customer deposits in the consolidated balance sheets as of June 30, 2015 and December 31, 2014 was $878,000 and $703,000, respectively, and relates to cash received from customers on sales for which the revenue recognition criteria had not been achieved, customer advances, as well as other less significant customer arrangements requiring the deferral of revenue.

Liquidity

As of June 30, 2015, the Company had approximately $25.0 million in cash and cash equivalents, and working capital of $64.9 million. The Company has a total of $5.9 million in debt outstanding to its previous lender as of June 30, 2015, which was paid in full on July 3, 2015. In July 2015, the Company entered into a loan agreement with East West Bank (“EWB”), whereby EWB made available to the Company a secured credit facility in the form of a revolving line of credit which is available up to a maximum of the lesser of: (a) $25.0 million; or (b) a certain percentage of domestic and foreign trade receivables. Management believes the available cash balance, along with the available borrowings under the revolving line of credit, will be sufficient to fund its operations, obligations as they become due, and capital investments for at least the next twelve months.

Net Loss per Share

In accordance with the Earnings Per Share Topic of the FASB ASC, basic net income (loss) per share is calculated using the weighted average number of common shares outstanding during the period. Diluted net income per share includes the impact of additional common shares that would have been outstanding if potentially dilutive common shares were issued. Potentially dilutive securities are not considered in the calculation of diluted net loss per share, as their inclusion would be anti-dilutive.

Restructuring and Exit Costs

Restructuring and exit costs involve employee-related termination costs, facility exit costs and other costs associated with our restructuring activities. The Company accounts for charges resulting from operational restructuring actions in accordance with ASC Topic 420, Exit or Disposal Cost Obligations (“ASC 420”) and ASC Topic 712, Compensation-Nonretirement Postemployment Benefits (“ASC 712”).

The recognition of restructuring costs require that the Company make certain assumptions related to the amounts of employee severance benefits, the time period over which leased facilities will remain vacant, expected sublease terms and discount rates. Estimates and assumptions are based on the best information available at the time the obligation arises. These estimates are reviewed and revised as facts and circumstances dictate; changes in these estimates could have a material effect on the amount accrued in the consolidated balance sheet.

Fair Value Measurements and Disclosures

The Company records certain financial instruments at fair value in accordance with the Fair Value Measurements and Disclosures Topic of the FASB ASC. As of June 30, 2015, the financial instruments to which this topic applied were foreign currency forward contracts. As of June 30, 2015, the fair value of these foreign currency forward contracts was a liability of $167,000 which is recorded in “accounts payable and accrued liabilities" in the consolidated balance sheet. The fair value of these derivative instruments is measured using models following quoted market prices in active markets for identical instruments, which is a Level 2 input under the fair value hierarchy of the Fair Value Measurements and Disclosures Topic of the FASB ASC.

Derivatives and Hedging

Maxwell uses forward contracts to hedge certain monetary assets and liabilities, primarily receivables and payables, denominated in foreign currencies. The change in fair value of these forward contracts represents a natural hedge as gains and losses on these instruments partially offset the changes in the fair value of the underlying monetary assets and liabilities due to movements in currency exchange rates. These forward contracts generally expire in one month. These contracts are considered economic hedges but are not designated as hedges under the Derivatives and Hedging Topic of the FASB ASC, therefore, the change in the fair value of the instrument is recognized each period in the consolidated statement of operations.