Note 1. Organization and Summary of Significant Accounting Policies	6 Months Ended
Aug. 03, 2013
Accounting Policies [Abstract]
Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block]	1. Organization and summary of significant accounting policies Organization and nature of operations: Sigma Designs, Inc. (referred to collectively in these interim condensed consolidated financial statements as “Sigma,” “we,” “our”, “the Company” and “us”) is a leader in connected media platforms. We specialize in digital television, or DTV, media processors and chipset solutions that serve as the foundation for some of the world’s leading internet protocol television, or IPTV, set-top-boxes, connected media players, residential gateways and home control systems. We sell our products to manufacturers, designers and, to a lesser extent, to distributors who, in turn, sell to manufacturers. Basis of presentation: The interim condensed consolidated financial statements include Sigma Designs, Inc. and its wholly-owned subsidiaries. All intercompany balances and transactions are eliminated upon consolidation. We operate and report quarterly financial results that consist of 13 weeks and end on the last Saturday of the period. The second quarter of fiscal 2014 and fiscal 2013 ended on August 3, 2013 (91 days) and July 28, 2012 (91 days), respectively. The unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America, or US GAAP, for interim financial information and the rules and regulations of the Securities and Exchange Commission, or SEC. They do not include all disclosures required by US GAAP for complete financial statements. Therefore, these financial statements should be read in conjunction with our audited consolidated financial statements and notes thereto for the year ended February 2, 2013, included in our fiscal 2013 Annual Report on Form 10-K, as filed with the SEC on April 12, 2013, referred to as our fiscal 2013 Annual Report. The condensed consolidated financial statements included herein are unaudited; however, they contain all normal recurring accruals and adjustments that, in our opinion, are necessary to present fairly our consolidated financial position at August 3, 2013 and February 2, 2013, the consolidated results of our operations for the three and six months ended August 3, 2013 and July 28, 2012, and the consolidated cash flows for the six months ended August 3, 2013 and July 28, 2012. The results of operations for the three and six months ended August 3, 2013 are not necessarily indicative of the results to be expected for future quarters or the full year. There have been no significant changes in our critical accounting policies during the six months ended August 3, 2013, as compared to the critical accounting policies described in our Annual Report on Form 10-K for the year ended February 2, 2013. For a complete summary of our significant accounting policies, refer to Note 1, "Organization and Summary of Significant Accounting Policies”, in Part II, Item 8 of our fiscal 2013 Annual Report. Use of estimates: The preparation of the consolidated financial statements in conformity with accounting principles generally accepted in the United States of America, or US GAAP, requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosures of contingent liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. The primary areas that require significant estimates and judgments by management include, but are not limited to, revenue recognition, allowances for doubtful accounts, sales returns, warranty obligations, inventory valuation, stock-based compensation expense, goodwill and purchased intangible asset valuations, strategic investments, deferred income tax asset valuation allowances, uncertain tax positions, tax contingencies, restructuring costs, litigation and other loss contingencies. These estimates and assumptions are based on historical experience and various other factors that we believe to be reasonable under the circumstances. Actual results could differ from those estimates, and such differences may be material to our consolidated financial statements. Business combinations: In May 2012, we completed our acquisition of certain assets from Trident Microsystems, Inc. and certain of its subsidiaries (collectively referred to as “Trident”). The consolidated financial statements include the results of operations of Trident commencing as of the acquisition date. Refer to Note 10, "Business combinations”, in Part II, Item 8 of our fiscal 2013 Annual Report. Recent Accounting Pronouncements In July 2013, the FASB issued ASU No. 2013-11, Income Taxes (Topic 740), Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carry forward, a Similar Tax Loss, or a Tax Credit Carry forward Exists (a consensus of the FASB Emerging Issues Task Force). U.S. GAAP does not include explicit guidance on the financial statement presentation of an unrecognized tax benefit when a net operating loss carry forward, a similar tax loss, or a tax credit carry forward exists. The amendments in this ASU state that an unrecognized tax benefit, or a portion of an unrecognized tax benefit, should be presented in the financial statements as a reduction to a deferred tax asset for a net operating loss carry forward, a similar tax loss, or a tax credit carry forward, except as follows. To the extent a net operating loss carry forward, a similar tax loss, or a tax credit carry forward is not available at the reporting date under the tax law of the applicable jurisdiction to settle any additional income taxes that would result from the disallowance of a tax position or the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose, the unrecognized tax benefit should be presented in the financial statements as a liability and should not be combined with deferred tax assets. This ASU applies to all entities that have unrecognized tax benefits when a net operating loss carry forward, a similar tax loss, or a tax credit carry forward exists at the reporting date. The amendments in this ASU are effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. Early adoption is permitted. The amendments should be applied prospectively to all unrecognized tax benefits that exist at the effective date. Retrospective application is permitted. In July 2012, the FASB issued Accounting Standards Update No. 2012-02, Intangibles—Goodwill and Other (Topic 350)—Testing Indefinite-Lived Intangible Assets for Impairment (ASU 2012-02), to allow entities to use a qualitative approach to test indefinite-lived intangible assets for impairment. ASU 2012-02 permits an entity to first perform a qualitative assessment to determine whether it is more likely than not that the fair value of an indefinite-lived intangible asset is less than its carrying value. If it is concluded that this is the case, it is necessary to perform the currently prescribed quantitative impairment test by comparing the fair value of the indefinite-lived intangible asset with its carrying value. Otherwise, the quantitative impairment test is not required. ASU 2012-02 is effective for us in our fiscal 2014 and earlier adoption is permitted. We are currently evaluating the impact of our pending adoption of ASU 2012-02 on our consolidated financial statements.

Note 1. Organization and Summary of Significant Accounting Policies

6 Months Ended

Aug. 03, 2013

Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block]

1. Organization and summary of significant accounting policies

Organization and nature of operations: Sigma Designs, Inc. (referred to collectively in these interim condensed consolidated financial statements as “Sigma,” “we,” “our”, “the Company” and “us”) is a leader in connected media platforms. We specialize in digital television, or DTV, media processors and chipset solutions that serve as the foundation for some of the world’s leading internet protocol television, or IPTV, set-top-boxes, connected media players, residential gateways and home control systems. We sell our products to manufacturers, designers and, to a lesser extent, to distributors who, in turn, sell to manufacturers.

Basis of presentation: The interim condensed consolidated financial statements include Sigma Designs, Inc. and its wholly-owned subsidiaries. All intercompany balances and transactions are eliminated upon consolidation. We operate and report quarterly financial results that consist of 13 weeks and end on the last Saturday of the period. The second quarter of fiscal 2014 and fiscal 2013 ended on August 3, 2013 (91 days) and July 28, 2012 (91 days), respectively.

The unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America, or US GAAP, for interim financial information and the rules and regulations of the Securities and Exchange Commission, or SEC. They do not include all disclosures required by US GAAP for complete financial statements. Therefore, these financial statements should be read in conjunction with our audited consolidated financial statements and notes thereto for the year ended February 2, 2013, included in our fiscal 2013 Annual Report on Form 10-K, as filed with the SEC on April 12, 2013, referred to as our fiscal 2013 Annual Report.

The condensed consolidated financial statements included herein are unaudited; however, they contain all normal recurring accruals and adjustments that, in our opinion, are necessary to present fairly our consolidated financial position at August 3, 2013 and February 2, 2013, the consolidated results of our operations for the three and six months ended August 3, 2013 and July 28, 2012, and the consolidated cash flows for the six months ended August 3, 2013 and July 28, 2012. The results of operations for the three and six months ended August 3, 2013 are not necessarily indicative of the results to be expected for future quarters or the full year.

There have been no significant changes in our critical accounting policies during the six months ended August 3, 2013, as compared to the critical accounting policies described in our Annual Report on Form 10-K for the year ended February 2, 2013. For a complete summary of our significant accounting policies, refer to Note 1, "Organization and Summary of Significant Accounting Policies”, in Part II, Item 8 of our fiscal 2013 Annual Report.

Use of estimates: The preparation of the consolidated financial statements in conformity with accounting principles generally accepted in the United States of America, or US GAAP, requires us to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosures of contingent liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. The primary areas that require significant estimates and judgments by management include, but are not limited to, revenue recognition, allowances for doubtful accounts, sales returns, warranty obligations, inventory valuation, stock-based compensation expense, goodwill and purchased intangible asset valuations, strategic investments, deferred income tax asset valuation allowances, uncertain tax positions, tax contingencies, restructuring costs, litigation and other loss contingencies. These estimates and assumptions are based on historical experience and various other factors that we believe to be reasonable under the circumstances. Actual results could differ from those estimates, and such differences may be material to our consolidated financial statements.

Business combinations: In May 2012, we completed our acquisition of certain assets from Trident Microsystems, Inc. and certain of its subsidiaries (collectively referred to as “Trident”). The consolidated financial statements include the results of operations of Trident commencing as of the acquisition date. Refer to Note 10, "Business combinations”, in Part II, Item 8 of our fiscal 2013 Annual Report.

Recent Accounting Pronouncements

In July 2013, the FASB issued ASU No. 2013-11, Income Taxes (Topic 740), Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carry forward, a Similar Tax Loss, or a Tax Credit Carry forward Exists (a consensus of the FASB Emerging Issues Task Force). U.S. GAAP does not include explicit guidance on the financial statement presentation of an unrecognized tax benefit when a net operating loss carry forward, a similar tax loss, or a tax credit carry forward exists. The amendments in this ASU state that an unrecognized tax benefit, or a portion of an unrecognized tax benefit, should be presented in the financial statements as a reduction to a deferred tax asset for a net operating loss carry forward, a similar tax loss, or a tax credit carry forward, except as follows. To the extent a net operating loss carry forward, a similar tax loss, or a tax credit carry forward is not available at the reporting date under the tax law of the applicable jurisdiction to settle any additional income taxes that would result from the disallowance of a tax position or the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose, the unrecognized tax benefit should be presented in the financial statements as a liability and should not be combined with deferred tax assets. This ASU applies to all entities that have unrecognized tax benefits when a net operating loss carry forward, a similar tax loss, or a tax credit carry forward exists at the reporting date. The amendments in this ASU are effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. Early adoption is permitted. The amendments should be applied prospectively to all unrecognized tax benefits that exist at the effective date. Retrospective application is permitted.

In July 2012, the FASB issued Accounting Standards Update No. 2012-02, Intangibles—Goodwill and Other (Topic 350)—Testing Indefinite-Lived Intangible Assets for Impairment (ASU 2012-02), to allow entities to use a qualitative approach to test indefinite-lived intangible assets for impairment. ASU 2012-02 permits an entity to first perform a qualitative assessment to determine whether it is more likely than not that the fair value of an indefinite-lived intangible asset is less than its carrying value. If it is concluded that this is the case, it is necessary to perform the currently prescribed quantitative impairment test by comparing the fair value of the indefinite-lived intangible asset with its carrying value. Otherwise, the quantitative impairment test is not required. ASU 2012-02 is effective for us in our fiscal 2014 and earlier adoption is permitted. We are currently evaluating the impact of our pending adoption of ASU 2012-02 on our consolidated financial statements.