BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES	9 Months Ended
Sep. 27, 2015
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES Nature of Operations Mattson Technology, Inc. (referred to in this Quarterly Report on Form 10-Q as "Mattson," "we," "us," or "our") was incorporated in California in 1988 and reincorporated in Delaware in 1997. We design, manufacture, market and globally support semiconductor wafer processing equipment used in the fabrication of integrated circuits. Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") for interim financial information and with the instructions to Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by such accounting principles for complete financial statements. In the opinion of management, all adjustments (which include normal recurring adjustments) considered necessary to present fairly each of the statement of financial position as of September 27, 2015, the statements of operations for the three and nine months ended September 27, 2015 and September 28, 2014, statements of comprehensive income for the three and nine months ended September 27, 2015 and September 28, 2014, and the statements of cash flows for the nine months ended September 27, 2015 and September 28, 2014, as applicable, have been made. The condensed consolidated balance sheet as of December 31, 2014 has been derived from our audited financial statements as of such date, but does not include all disclosures required by U.S. GAAP. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with our audited consolidated financial statements for the year ended December 31, 2014, which are included in the Annual Report on Form 10-K filed with the Securities and Exchange Commission ("SEC") on March 12, 2015. The condensed consolidated financial statements include the accounts of Mattson Technology, Inc. and our wholly-owned subsidiaries. All inter-company balances and transactions have been eliminated. The results of operations for the three and nine months ended September 27, 2015 are not necessarily indicative of results that may be expected for the entire year ending December 31, 2015. Fiscal Year Our fiscal year ends on December 31. We close our first fiscal quarter on the Sunday closest to March 31. Our second and third fiscal quarters are each 13 weeks long and our fourth quarter closes on December 31. Use of Estimates The preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reported periods. We evaluate our estimates on an ongoing basis, including those related to the useful lives and fair value of long-lived assets, estimates used to determine facility lease loss liabilities, measurement of warranty obligations, valuation allowances for deferred tax assets, the fair value of stock-based compensation, estimates for allowance for doubtful accounts, and valuation of excess and obsolete inventories. Our estimates and assumptions can be subjective and complex and, consequently, actual results could differ materially from those estimates. Reclassifications For presentation purposes, certain prior period amounts have been reclassified to conform to the reporting in the current period financial statements. These reclassifications do not affect our net income, cash flows or stockholders' equity. Recent Accounting Pronouncements In April 2015, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2015-03, Simplifying the Presentation of Debt Issuance Costs. Debt issuance costs are specified incremental costs, other than those paid to the lender, that are directly attributable to issuing a debt instrument (i.e., third party costs). Prior to the adoption of this standard, debt issuance costs were required to be presented in the balance sheet as a deferred charge (i.e., an asset). This presentation differed from the presentation for a debt discount, which is a direct adjustment to the carrying value of the debt (i.e., a contra liability). This new standard requires that all costs incurred to issue debt be presented in the balance sheet as a direct deduction from the carrying value of the debt. This guidance will be effective for us in the first quarter of fiscal 2016, with early adoption permitted. We do not expect the adoption of this accounting standard to have a material impact on our financial statements and footnote disclosures. In August 2015, the FASB issued ASU No. 2015-15, Interest – Imputation of Interest: Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements. ASU 2015-15 provides additional guidance to ASU 2015-03, which did not address presentation or subsequent measurement of debt issuance costs related to line of credit arrangements. ASU 2015-15 noted that the SEC staff would not object to an entity deferring and presenting debt issuance costs as an asset and subsequently amortizing the deferred debt issuance costs ratably over the term of the line of credit arrangement, regardless of whether there are any outstanding borrowings on the line of credit arrangement. As of September 27, 2015, we continue to record our unamortized debt issuance costs in connection with our revolving credit facility as an asset. In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers. The FASB issued ASU 2014-09 to clarify the principles for recognizing revenue and to develop a common revenue standard for GAAP and International Financial Reporting Standards. The standard outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes the most current revenue recognition guidance. In August 2015, the FASB issued ASU No. 2015-14, Revenue from Contracts with Customers: Deferral of the Effective Date, deferring the effective date of ASU 2014-09 by one year. This guidance will be effective for us in the first quarter of fiscal 2018, with early adoption permitted for annual periods beginning after December 15, 2016. We are currently evaluating the impact that the implementation of this standard will have on our financial statements and footnote disclosures. In July 2015, the FASB issued ASU No. 2015-11, Inventory: Simplifying the Measurement of Inventory. Under ASU 2015-11, we are required to measure inventory at the lower of cost and net realizable value. The new guidance clarifies that net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal and transportation. This guidance is effective for us in the first quarter of fiscal 2017, with early adoption permitted. We are currently evaluating the impact that the implementation of this standard will have on our financial statements and footnote disclosures. In August 2014, the FASB issued ASU No. 2014-15, Presentation of Financial Statements—Going Concern. The update provides U.S. GAAP guidance on management’s responsibility in evaluating whether there is substantial doubt about a company’s ability to continue as a going concern and about related footnote disclosures. For each reporting period, management will be required to evaluate whether there are conditions or events that raise substantial doubt about a company’s ability to continue as a going concern within one year from the date the financial statements are issued. This guidance is effective for us beginning with our annual financial statements for fiscal 2017. We are currently evaluating the impact that the implementation of this standard will have on our financial statements and footnote disclosures. There were no other recent accounting pronouncements or changes in accounting pronouncements during the nine months ended September 27, 2015 compared to the recent accounting pronouncements described in our Annual Report on Form 10-K for the fiscal year ended December 31, 2014 that are of significance or potential significance to us.

BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES

Nature of Operations

Mattson Technology, Inc. (referred to in this Quarterly Report on Form 10-Q as "Mattson," "we," "us," or "our") was incorporated in California in 1988 and reincorporated in Delaware in 1997. We design, manufacture, market and globally support semiconductor wafer processing equipment used in the fabrication of integrated circuits.

Basis of Presentation

The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America ("U.S. GAAP") for interim financial information and with the instructions to Article 10 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by such accounting principles for complete financial statements. In the opinion of management, all adjustments (which include normal recurring adjustments) considered necessary to present fairly each of the statement of financial position as of September 27, 2015, the statements of operations for the three and nine months ended September 27, 2015 and September 28, 2014, statements of comprehensive income for the three and nine months ended September 27, 2015 and September 28, 2014, and the statements of cash flows for the nine months ended September 27, 2015 and September 28, 2014, as applicable, have been made. The condensed consolidated balance sheet as of December 31, 2014 has been derived from our audited financial statements as of such date, but does not include all disclosures required by U.S. GAAP. The accompanying unaudited condensed consolidated financial statements should be read in conjunction with our audited consolidated financial statements for the year ended December 31, 2014, which are included in the Annual Report on Form 10-K filed with the Securities and Exchange Commission ("SEC") on March 12, 2015.

The condensed consolidated financial statements include the accounts of Mattson Technology, Inc. and our wholly-owned subsidiaries. All inter-company balances and transactions have been eliminated.

The results of operations for the three and nine months ended September 27, 2015 are not necessarily indicative of results that may be expected for the entire year ending December 31, 2015.

Fiscal Year

Our fiscal year ends on December 31. We close our first fiscal quarter on the Sunday closest to March 31. Our second and third fiscal quarters are each 13 weeks long and our fourth quarter closes on December 31.

Use of Estimates

The preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reported periods. We evaluate our estimates on an ongoing basis, including those related to the useful lives and fair value of long-lived assets, estimates used to determine facility lease loss liabilities, measurement of warranty obligations, valuation allowances for deferred tax assets, the fair value of stock-based compensation, estimates for allowance for doubtful accounts, and valuation of excess and obsolete inventories. Our estimates and assumptions can be subjective and complex and, consequently, actual results could differ materially from those estimates.

Reclassifications

For presentation purposes, certain prior period amounts have been reclassified to conform to the reporting in the current period financial statements. These reclassifications do not affect our net income, cash flows or stockholders' equity.

Recent Accounting Pronouncements

In April 2015, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2015-03, Simplifying the Presentation of Debt Issuance Costs. Debt issuance costs are specified incremental costs, other than those paid to the lender, that are directly attributable to issuing a debt instrument (i.e., third party costs). Prior to the adoption of this standard, debt issuance costs were required to be presented in the balance sheet as a deferred charge (i.e., an asset). This presentation differed from the presentation for a debt discount, which is a direct adjustment to the carrying value of the debt (i.e., a contra liability). This new standard requires that all costs incurred to issue debt be presented in the balance sheet as a direct deduction from the carrying value of the debt. This guidance will be effective for us in the first quarter of fiscal 2016, with early adoption permitted. We do not expect the adoption of this accounting standard to have a material impact on our financial statements and footnote disclosures. In August 2015, the FASB issued ASU No. 2015-15, Interest – Imputation of Interest: Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements. ASU 2015-15 provides additional guidance to ASU 2015-03, which did not address presentation or subsequent measurement of debt issuance costs related to line of credit arrangements. ASU 2015-15 noted that the SEC staff would not object to an entity deferring and presenting debt issuance costs as an asset and subsequently amortizing the deferred debt issuance costs ratably over the term of the line of credit arrangement, regardless of whether there are any outstanding borrowings on the line of credit arrangement. As of September 27, 2015, we continue to record our unamortized debt issuance costs in connection with our revolving credit facility as an asset.

In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers. The FASB issued ASU 2014-09 to clarify the principles for recognizing revenue and to develop a common revenue standard for GAAP and International Financial Reporting Standards. The standard outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes the most current revenue recognition guidance. In August 2015, the FASB issued ASU No. 2015-14, Revenue from Contracts with Customers: Deferral of the Effective Date, deferring the effective date of ASU 2014-09 by one year. This guidance will be effective for us in the first quarter of fiscal 2018, with early adoption permitted for annual periods beginning after December 15, 2016. We are currently evaluating the impact that the implementation of this standard will have on our financial statements and footnote disclosures.

In July 2015, the FASB issued ASU No. 2015-11, Inventory: Simplifying the Measurement of Inventory. Under ASU 2015-11, we are required to measure inventory at the lower of cost and net realizable value. The new guidance clarifies that net realizable value is the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal and transportation. This guidance is effective for us in the first quarter of fiscal 2017, with early adoption permitted. We are currently evaluating the impact that the implementation of this standard will have on our financial statements and footnote disclosures.

In August 2014, the FASB issued ASU No. 2014-15, Presentation of Financial Statements—Going Concern. The update provides U.S. GAAP guidance on management’s responsibility in evaluating whether there is substantial doubt about a company’s ability to continue as a going concern and about related footnote disclosures. For each reporting period, management will be required to evaluate whether there are conditions or events that raise substantial doubt about a company’s ability to continue as a going concern within one year from the date the financial statements are issued. This guidance is effective for us beginning with our annual financial statements for fiscal 2017. We are currently evaluating the impact that the implementation of this standard will have on our financial statements and footnote disclosures.

There were no other recent accounting pronouncements or changes in accounting pronouncements during the nine months ended September 27, 2015 compared to the recent accounting pronouncements described in our Annual Report on Form 10-K for the fiscal year ended December 31, 2014 that are of significance or potential significance to us.