Organization and Summary of Significant Accounting Policies	12 Months Ended
Dec. 28, 2014
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization, Consolidation and Presentation of Financial Statements Disclosure	Organization and Summary of Significant Accounting Policies Organization and Nature of Operations. SanDisk Corporation (together with its subsidiaries, the “Company”) was incorporated in the State of Delaware on June 1, 1988. The Company designs, develops, markets and manufactures data storage solutions in a variety of form factors using its flash memory, controller and firmware technologies. The Company operates in one segment, flash memory storage products. Basis of Presentation. The Company’s fiscal year ends on the Sunday closest to December 31. Fiscal years 2014, 2013 and 2012 consisted of 52 weeks, while fiscal year 2015 will include 53 weeks with 14 weeks in the fourth fiscal quarter. Certain prior-period amounts have been reclassified in the footnotes to conform to the current-period presentation, including line items within other current and non-current assets and liabilities, and warranties in Note 5, “Balance Sheet Information.” For accounting and disclosure purposes, the exchange rate used to convert Japanese yen to the United States (“U.S.”) dollar for fiscal years ended December 28, 2014, December 29, 2013 and December 30, 2012 was 120.44, 104.94 and 85.99, respectively. Throughout the Notes to Consolidated Financial Statements, unless otherwise indicated, references to Net income refer to Net income attributable to common stockholders. Principles of Consolidation. The Consolidated Financial Statements include the accounts of the Company and its majority-owned subsidiaries. All intercompany balances and transactions have been eliminated. Non-controlling interest represents the minority stockholders’ proportionate share of the net assets and results of operations of the Company’s majority-owned subsidiaries. The Consolidated Financial Statements also include the results of companies acquired by the Company from the date of each acquisition. Use of Estimates. The preparation of Consolidated Financial Statements in conformity with U.S. generally accepted accounting principles (“GAAP”) requires management to make estimates and assumptions that affect the amounts reported in the Consolidated Financial Statements and accompanying notes. The estimates and judgments affect the reported amounts of assets, liabilities, revenue, expenses and related disclosure of contingent liabilities. On an ongoing basis, the Company evaluates its estimates, including those related to customer programs and incentives, intellectual property (“IP”) claims, product returns, allowance for doubtful accounts, inventories and inventory valuation, valuation and impairments of marketable securities and investments, valuation and impairments of goodwill and long-lived assets, income taxes, warranty obligations, restructurings, contingencies, share‑based compensation and litigation. The Company bases its estimates on historical experience and on other assumptions that its management believes are reasonable under the circumstances. These estimates form the basis for making judgments about the carrying value of assets and liabilities when those values are not readily apparent from other sources. Actual results could materially differ from these estimates. Revenue Recognition, Sales Returns and Allowances and Sales Incentive Programs. The Company recognizes revenue when the earnings process is complete, as evidenced by an agreement with the customer, transfer of title and acceptance, if applicable, pricing is fixed or determinable and collectability is reasonably assured. Revenue is generally recognized at the time of shipment or transfer of title for customers not eligible for price protection and/or a right of return. Sales made to distributors and retailers are generally under agreements allowing price protection and/or a right of return and, therefore, the revenue and related costs of these transactions are deferred until the retailers or distributors sell-through the merchandise to their end customer or their rights of return expire. Estimated sales returns are recorded as a reduction to revenue and deferred revenue and were not material for any period presented in the accompanying Consolidated Financial Statements. The cost of shipping products to customers is included in cost of revenue. The Company recognizes expenses related to sales commissions in the period in which the commissions are earned. For multiple-element arrangements that include support or software elements, the Company analyzes whether tangible products containing software and non-software components function together and therefore should be excluded from industry-specific software revenue recognition guidance. The Company allocates revenue to each element, or the software elements as a group, based on the relative selling price determined in accordance with the Company’s normal pricing and discounting practices for the specific element when sold separately for all multiple-element arrangements. Multiple-element arrangements and arrangements that include software have not been significant to the Company’s revenue and operating results. Revenue from patent licensing arrangements is recognized when earned, estimable and realizable. The timing of revenue recognition is dependent on the terms of each license agreement and on the timing of sales of licensed products. The Company generally recognizes royalty revenue when it is reported to the Company by its licensees, which is generally one quarter in arrears from the licensees’ sales of licensed products. For licensing fees that are not determined by the number of licensed units sold, the Company recognizes license fee revenue on a straight-line basis over the life of the license. The Company records estimated reductions of revenue for customer and distributor incentive programs and offerings, including price protection, promotions, co-op advertising and other volume-based incentives and expected returns. All sales incentive programs are recorded as an offset to revenue or deferred revenue. Marketing development programs are recorded as a reduction to revenue. Accounts Receivable and Allowance for Doubtful Accounts. Accounts receivable include amounts owed by geographically dispersed distributors, retailers and original equipment manufacturer (“OEM”) customers. No collateral is required. Provisions are provided for sales returns and credit losses. The Company estimates the collectability of its accounts receivable based on a combination of factors including, but not limited to, customer credit ratings and historical experience. In circumstances where the Company is aware of a specific customer’s inability to meet its financial obligations to the Company (e.g., bankruptcy filings or substantial downgrading of credit ratings), the Company provides allowances for bad debts against amounts due to reduce the net recognized receivable to the amount it reasonably believes will be collected. Income Taxes. The Company accounts for income taxes using an asset and liability approach, which requires recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the Company’s Consolidated Financial Statements, but have not been reflected in the Company’s taxable income. The Company must evaluate the expected realization of its deferred tax assets and determine whether a valuation allowance needs to be established or released. In determining the need for and amount of a valuation allowance, the Company assesses the likelihood that it will be able to recover its deferred tax assets using historical levels of income, estimates of future income and tax planning strategies. A valuation allowance is established to the extent that the Company does not believe it is “more likely than not” that it will generate sufficient taxable income in future periods to realize the benefit of its deferred tax assets. The Company recognizes interest and penalties related to unrecognized tax benefits in income tax expense. The Company recognizes the tax benefit from an uncertain tax position only if it is “more likely than not” the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The tax benefits recognized in the financial statements from such positions are then measured based on the largest benefit that has a greater than 50% likelihood of being realized upon settlement. Foreign Currency. The Company determines the functional currency for its parent company and each of its subsidiaries by reviewing the currencies in which their respective operating activities occur. Transaction gains and losses arising from activities in other than the applicable functional currency are calculated using average exchange rates for the applicable period and reported in net income as a non-operating item in each period. Non-monetary balance sheet items denominated in a currency other than the applicable functional currency are translated using the historical rate. The Company continuously evaluates its foreign currency exposures and may continue to enter into hedges or other risk mitigating arrangements in the future. Aggregate gross foreign currency transaction gain (loss) prior to consideration of the offsetting hedges recorded to income before taxes was $3.1 million, ($3.3) million and ($2.8) million in fiscal years 2014, 2013 and 2012, respectively. Cash Equivalents, Short and Long-Term Marketable Securities. Cash equivalents consist of short-term, highly liquid financial instruments with insignificant interest rate risk that are readily convertible to cash and have maturities of three months or less from the date of purchase. Marketable securities with original maturities greater than three months from purchase date and remaining maturities less than one year are classified as short-term marketable securities. Marketable securities with remaining maturities greater than one year as of the balance sheet date are classified as long-term marketable securities. Short and long-term fixed income investments consist of U.S. Treasury securities, U.S. government-sponsored agency securities, international government securities, corporate notes and bonds, asset-backed securities, mortgage-backed securities and municipal notes and bonds. The fair market value of cash equivalents at December 28, 2014 approximated their carrying value. Cost of securities sold is based on specific identification. In determining if and when a decline in market value below cost of these investments is other-than-temporary, the Company evaluates both quantitative and qualitative information including the market conditions, offering prices, trends of earnings, price multiples and other key measures. For fixed income securities, only the decline attributable to deteriorating credit of an other-than-temporary impairment is taken to the Consolidated Statement of Operations, unless the Company intends, or “more likely than not” will be required, to sell the security. Property and Equipment. Property and equipment are carried at cost less accumulated depreciation and amortization. Depreciation and amortization are computed using the straight-line method over the estimated useful lives of the assets, ranging from two to twenty-five years, or the remaining lease term, whichever is shorter. Variable Interest Entities. The Company evaluates its equity method investments to determine whether any investee is a variable interest entity (“VIE”). If the Company concludes that an investee is a VIE, the Company evaluates its power to direct the activities of the investee, its obligation to absorb the expected losses of the investee and its right to receive the expected residual returns of the investee to determine whether the Company is the primary beneficiary of the investee. If the Company is the primary beneficiary of a VIE, the Company consolidates such entity and reflects the non-controlling interest of other beneficiaries of that entity. If the Company concludes that an investee is not a VIE, the Company does not consolidate the investee. Equity Investments. The Company accounts for investments in equity securities of other entities, including VIEs that are not consolidated, under the cost method of accounting if investments in voting equity interests of the investee are less than 20%. The equity method of accounting is used if the Company’s investment in voting stock is greater than or equal to 20% but less than a majority. In considering the accounting method for investments less than 20%, the Company also considers other factors such as its ability to exercise significant influence over operating and financial policies of the investee. If certain factors are present, the Company could account for investments for which it has less than a 20% ownership under the equity method of accounting. Investments in public companies with restrictions of less than one year are classified as available-for-sale and are adjusted to their fair market value with unrealized gains and losses recorded as a component of accumulated other comprehensive income (“AOCI”). Investments in public and non-public companies are reviewed on a quarterly basis to determine if their value has been impaired and adjustments are recorded as necessary. Upon disposition of these investments, the specific identification method is used to determine the cost basis in computing realized gains or losses. Declines in value that are judged to be other-than-temporary are reported in Interest (expense) and other income (expense), net, or Cost of revenue in the accompanying Consolidated Statements of Operations. Inventories and Inventory Valuation. Inventories are stated at the lower of cost (first-in, first-out) or market. Market value is based upon an estimated average selling price reduced by estimated costs of disposal. Should actual market conditions differ from the Company’s estimates, the Company’s future results of operations could be materially affected. Reductions in inventory valuation are included in Cost of revenue in the accompanying Consolidated Statements of Operations. Inventory impairment charges, when taken, permanently establish a new cost basis and are not subsequently reversed to income even if circumstances later suggest that increased carrying amounts are recoverable. Rather, these amounts are recognized in income only if, as and when the inventory is sold. The Company reduces the carrying value of its inventory to a new basis for estimated obsolescence or unmarketable inventory by an amount equal to the difference between the cost of the inventory and the estimated market value based upon assumptions about future demand and market conditions, including assumptions about changes in average selling prices. If actual market conditions are less favorable than those projected by management, additional reductions in inventory valuation may be required. The Company’s finished goods inventory includes consigned inventory held at customer locations as well as at third‑party fulfillment centers and subcontractors. Other Long-Lived Assets. Intangible assets with finite useful lives and other long-lived assets are tested for impairment if certain impairment indicators are identified. The Company assesses the carrying value of long-lived assets, whenever events or changes in circumstances indicate that the carrying value of these long-lived assets may not be recoverable. Factors the Company considers important which could result in an impairment review include: (1) significant under-performance relative to the historical or projected future operating results; (2) significant changes in the manner of use of assets; (3) significant negative industry or economic trends; and (4) significant changes in the Company’s market capitalization relative to net book value. Any changes in key assumptions used by the Company, including those set forth above, could result in an impairment charge and such a charge could have a material adverse effect on the Company’s consolidated results of operations. Advertising Expenses. Marketing co-op development programs, where the Company receives, or will receive, an identifiable benefit (e.g., goods or services) in exchange for the amount paid to its customer and the Company can reasonably estimate the fair value of the benefit it receives for the customer incentive payment, are classified, when granted, as a marketing expense. Advertising expenses not meeting this criteria are classified as a reduction to revenue when the expense is incurred. Advertising expenses recorded as marketing expense were $27.9 million, $19.6 million and $16.2 million in fiscal years 2014, 2013 and 2012, respectively. Research and Development Expenses. Research and development (“R&D”) expenditures are expensed as incurred.

Organization and Summary of Significant Accounting Policies

Organization and Nature of Operations. SanDisk Corporation (together with its subsidiaries, the “Company”) was incorporated in the State of Delaware on June 1, 1988. The Company designs, develops, markets and manufactures data storage solutions in a variety of form factors using its flash memory, controller and firmware technologies. The Company operates in one segment, flash memory storage products.

Basis of Presentation. The Company’s fiscal year ends on the Sunday closest to December 31. Fiscal years 2014, 2013 and 2012 consisted of 52 weeks, while fiscal year 2015 will include 53 weeks with 14 weeks in the fourth fiscal quarter. Certain prior-period amounts have been reclassified in the footnotes to conform to the current-period presentation, including line items within other current and non-current assets and liabilities, and warranties in Note 5, “Balance Sheet Information.” For accounting and disclosure purposes, the exchange rate used to convert Japanese yen to the United States (“U.S.”) dollar for fiscal years ended December 28, 2014, December 29, 2013 and December 30, 2012 was 120.44, 104.94 and 85.99, respectively. Throughout the Notes to Consolidated Financial Statements, unless otherwise indicated, references to Net income refer to Net income attributable to common stockholders.

Principles of Consolidation. The Consolidated Financial Statements include the accounts of the Company and its majority-owned subsidiaries. All intercompany balances and transactions have been eliminated. Non-controlling interest represents the minority stockholders’ proportionate share of the net assets and results of operations of the Company’s majority-owned subsidiaries. The Consolidated Financial Statements also include the results of companies acquired by the Company from the date of each acquisition.

Use of Estimates. The preparation of Consolidated Financial Statements in conformity with U.S. generally accepted accounting principles (“GAAP”) requires management to make estimates and assumptions that affect the amounts reported in the Consolidated Financial Statements and accompanying notes. The estimates and judgments affect the reported amounts of assets, liabilities, revenue, expenses and related disclosure of contingent liabilities. On an ongoing basis, the Company evaluates its estimates, including those related to customer programs and incentives, intellectual property (“IP”) claims, product returns, allowance for doubtful accounts, inventories and inventory valuation, valuation and impairments of marketable securities and investments, valuation and impairments of goodwill and long-lived assets, income taxes, warranty obligations, restructurings, contingencies, share‑based compensation and litigation. The Company bases its estimates on historical experience and on other assumptions that its management believes are reasonable under the circumstances. These estimates form the basis for making judgments about the carrying value of assets and liabilities when those values are not readily apparent from other sources. Actual results could materially differ from these estimates.

Revenue Recognition, Sales Returns and Allowances and Sales Incentive Programs. The Company recognizes revenue when the earnings process is complete, as evidenced by an agreement with the customer, transfer of title and acceptance, if applicable, pricing is fixed or determinable and collectability is reasonably assured. Revenue is generally recognized at the time of shipment or transfer of title for customers not eligible for price protection and/or a right of return. Sales made to distributors and retailers are generally under agreements allowing price protection and/or a right of return and, therefore, the revenue and related costs of these transactions are deferred until the retailers or distributors sell-through the merchandise to their end customer or their rights of return expire. Estimated sales returns are recorded as a reduction to revenue and deferred revenue and were not material for any period presented in the accompanying Consolidated Financial Statements. The cost of shipping products to customers is included in cost of revenue. The Company recognizes expenses related to sales commissions in the period in which the commissions are earned.

For multiple-element arrangements that include support or software elements, the Company analyzes whether tangible products containing software and non-software components function together and therefore should be excluded from industry-specific software revenue recognition guidance. The Company allocates revenue to each element, or the software elements as a group, based on the relative selling price determined in accordance with the Company’s normal pricing and discounting practices for the specific element when sold separately for all multiple-element arrangements. Multiple-element arrangements and arrangements that include software have not been significant to the Company’s revenue and operating results.

Revenue from patent licensing arrangements is recognized when earned, estimable and realizable. The timing of revenue recognition is dependent on the terms of each license agreement and on the timing of sales of licensed products. The Company generally recognizes royalty revenue when it is reported to the Company by its licensees, which is generally one quarter in arrears from the licensees’ sales of licensed products. For licensing fees that are not determined by the number of licensed units sold, the Company recognizes license fee revenue on a straight-line basis over the life of the license.

The Company records estimated reductions of revenue for customer and distributor incentive programs and offerings, including price protection, promotions, co-op advertising and other volume-based incentives and expected returns. All sales incentive programs are recorded as an offset to revenue or deferred revenue. Marketing development programs are recorded as a reduction to revenue.

Accounts Receivable and Allowance for Doubtful Accounts. Accounts receivable include amounts owed by geographically dispersed distributors, retailers and original equipment manufacturer (“OEM”) customers. No collateral is required. Provisions are provided for sales returns and credit losses.

The Company estimates the collectability of its accounts receivable based on a combination of factors including, but not limited to, customer credit ratings and historical experience. In circumstances where the Company is aware of a specific customer’s inability to meet its financial obligations to the Company (e.g., bankruptcy filings or substantial downgrading of credit ratings), the Company provides allowances for bad debts against amounts due to reduce the net recognized receivable to the amount it reasonably believes will be collected.

Income Taxes. The Company accounts for income taxes using an asset and liability approach, which requires recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been recognized in the Company’s Consolidated Financial Statements, but have not been reflected in the Company’s taxable income. The Company must evaluate the expected realization of its deferred tax assets and determine whether a valuation allowance needs to be established or released. In determining the need for and amount of a valuation allowance, the Company assesses the likelihood that it will be able to recover its deferred tax assets using historical levels of income, estimates of future income and tax planning strategies. A valuation allowance is established to the extent that the Company does not believe it is “more likely than not” that it will generate sufficient taxable income in future periods to realize the benefit of its deferred tax assets.

The Company recognizes interest and penalties related to unrecognized tax benefits in income tax expense. The Company recognizes the tax benefit from an uncertain tax position only if it is “more likely than not” the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The tax benefits recognized in the financial statements from such positions are then measured based on the largest benefit that has a greater than 50% likelihood of being realized upon settlement.

Foreign Currency. The Company determines the functional currency for its parent company and each of its subsidiaries by reviewing the currencies in which their respective operating activities occur. Transaction gains and losses arising from activities in other than the applicable functional currency are calculated using average exchange rates for the applicable period and reported in net income as a non-operating item in each period. Non-monetary balance sheet items denominated in a currency other than the applicable functional currency are translated using the historical rate. The Company continuously evaluates its foreign currency exposures and may continue to enter into hedges or other risk mitigating arrangements in the future. Aggregate gross foreign currency transaction gain (loss) prior to consideration of the offsetting hedges recorded to income before taxes was $3.1 million, ($3.3) million and ($2.8) million in fiscal years 2014, 2013 and 2012, respectively.

Cash Equivalents, Short and Long-Term Marketable Securities. Cash equivalents consist of short-term, highly liquid financial instruments with insignificant interest rate risk that are readily convertible to cash and have maturities of three months or less from the date of purchase. Marketable securities with original maturities greater than three months from purchase date and remaining maturities less than one year are classified as short-term marketable securities. Marketable securities with remaining maturities greater than one year as of the balance sheet date are classified as long-term marketable securities. Short and long-term fixed income investments consist of U.S. Treasury securities, U.S. government-sponsored agency securities, international government securities, corporate notes and bonds, asset-backed securities, mortgage-backed securities and municipal notes and bonds. The fair market value of cash equivalents at December 28, 2014 approximated their carrying value. Cost of securities sold is based on specific identification.

In determining if and when a decline in market value below cost of these investments is other-than-temporary, the Company evaluates both quantitative and qualitative information including the market conditions, offering prices, trends of earnings, price multiples and other key measures. For fixed income securities, only the decline attributable to deteriorating credit of an other-than-temporary impairment is taken to the Consolidated Statement of Operations, unless the Company intends, or “more likely than not” will be required, to sell the security.

Property and Equipment. Property and equipment are carried at cost less accumulated depreciation and amortization. Depreciation and amortization are computed using the straight-line method over the estimated useful lives of the assets, ranging from two to twenty-five years, or the remaining lease term, whichever is shorter.

Variable Interest Entities. The Company evaluates its equity method investments to determine whether any investee is a variable interest entity (“VIE”). If the Company concludes that an investee is a VIE, the Company evaluates its power to direct the activities of the investee, its obligation to absorb the expected losses of the investee and its right to receive the expected residual returns of the investee to determine whether the Company is the primary beneficiary of the investee. If the Company is the primary beneficiary of a VIE, the Company consolidates such entity and reflects the non-controlling interest of other beneficiaries of that entity. If the Company concludes that an investee is not a VIE, the Company does not consolidate the investee.

Equity Investments. The Company accounts for investments in equity securities of other entities, including VIEs that are not consolidated, under the cost method of accounting if investments in voting equity interests of the investee are less than 20%. The equity method of accounting is used if the Company’s investment in voting stock is greater than or equal to 20% but less than a majority. In considering the accounting method for investments less than 20%, the Company also considers other factors such as its ability to exercise significant influence over operating and financial policies of the investee. If certain factors are present, the Company could account for investments for which it has less than a 20% ownership under the equity method of accounting.

Investments in public companies with restrictions of less than one year are classified as available-for-sale and are adjusted to their fair market value with unrealized gains and losses recorded as a component of accumulated other comprehensive income (“AOCI”). Investments in public and non-public companies are reviewed on a quarterly basis to determine if their value has been impaired and adjustments are recorded as necessary. Upon disposition of these investments, the specific identification method is used to determine the cost basis in computing realized gains or losses. Declines in value that are judged to be other-than-temporary are reported in Interest (expense) and other income (expense), net, or Cost of revenue in the accompanying Consolidated Statements of Operations.

Inventories and Inventory Valuation. Inventories are stated at the lower of cost (first-in, first-out) or market. Market value is based upon an estimated average selling price reduced by estimated costs of disposal. Should actual market conditions differ from the Company’s estimates, the Company’s future results of operations could be materially affected. Reductions in inventory valuation are included in Cost of revenue in the accompanying Consolidated Statements of Operations. Inventory impairment charges, when taken, permanently establish a new cost basis and are not subsequently reversed to income even if circumstances later suggest that increased carrying amounts are recoverable. Rather, these amounts are recognized in income only if, as and when the inventory is sold.

The Company reduces the carrying value of its inventory to a new basis for estimated obsolescence or unmarketable inventory by an amount equal to the difference between the cost of the inventory and the estimated market value based upon assumptions about future demand and market conditions, including assumptions about changes in average selling prices. If actual market conditions are less favorable than those projected by management, additional reductions in inventory valuation may be required.

The Company’s finished goods inventory includes consigned inventory held at customer locations as well as at third‑party fulfillment centers and subcontractors.

Other Long-Lived Assets. Intangible assets with finite useful lives and other long-lived assets are tested for impairment if certain impairment indicators are identified. The Company assesses the carrying value of long-lived assets, whenever events or changes in circumstances indicate that the carrying value of these long-lived assets may not be recoverable. Factors the Company considers important which could result in an impairment review include: (1) significant under-performance relative to the historical or projected future operating results; (2) significant changes in the manner of use of assets; (3) significant negative industry or economic trends; and (4) significant changes in the Company’s market capitalization relative to net book value. Any changes in key assumptions used by the Company, including those set forth above, could result in an impairment charge and such a charge could have a material adverse effect on the Company’s consolidated results of operations.

Advertising Expenses. Marketing co-op development programs, where the Company receives, or will receive, an identifiable benefit (e.g., goods or services) in exchange for the amount paid to its customer and the Company can reasonably estimate the fair value of the benefit it receives for the customer incentive payment, are classified, when granted, as a marketing expense. Advertising expenses not meeting this criteria are classified as a reduction to revenue when the expense is incurred. Advertising expenses recorded as marketing expense were $27.9 million, $19.6 million and $16.2 million in fiscal years 2014, 2013 and 2012, respectively.

Research and Development Expenses. Research and development (“R&D”) expenditures are expensed as incurred.