Organization and Basis of Presentation (Policies)	9 Months Ended
Apr. 02, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	Western Digital Corporation (“Western Digital” or the “Company”) is a leading developer, manufacturer, and provider of data storage devices and solutions that address the evolving needs of the information technology (“IT”) industry and the infrastructure that enables the proliferation of data in virtually every other industry. The Company creates environments for data to thrive. The Company is driving the innovation needed to help customers capture, preserve, access and transform an ever-increasing diversity of data. Everywhere data lives, from advanced data centers to mobile sensors to personal devices, the Company’s industry-leading solutions deliver the possibilities of data. The Company’s broad portfolio of technology and products address the following key end markets: Client Devices; Data Center Devices and Solutions; and Client Solutions. The Company also generates license and royalty revenue from its extensive intellectual property (“IP”), which is included in each of these three end market categories. The accounting policies followed by the Company are set forth in Part II, Item 8, Note 1, Organization and Basis of Presentation, of the Notes to Consolidated Financial Statements included in the Company’s Annual Report on Form 10‑K for the fiscal year ended July 3, 2020. In the opinion of management, all adjustments necessary to fairly state the Condensed Consolidated Financial Statements have been made. All such adjustments are of a normal, recurring nature. Certain information and footnote disclosures normally included in the Consolidated Financial Statements prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). These Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements and the notes thereto included in the Company’s Annual Report on Form 10‑K for the fiscal year ended July 3, 2020. The results of operations for interim periods are not necessarily indicative of results to be expected for the full year.
Fiscal Year	Fiscal YearThe Company’s fiscal year ends on the Friday nearest to June 30 and typically consists of 52 weeks. Approximately every five to six years, the Company reports a 53-week fiscal year to align the fiscal year with the foregoing policy. Fiscal year 2021, which ends on July 2, 2021, will be comprised of 52 weeks, with all quarters presented consisting of 13 weeks. Fiscal year 2020, which ended on July 3, 2020, was comprised of 53 weeks, with the first quarter consisting of 14 weeks and the remaining quarters consisting of 13 weeks each.
Use of Estimates	Use of Estimates Company management has made estimates and assumptions relating to the reporting of certain assets and liabilities in conformity with U.S. GAAP. These estimates and assumptions have been applied using methodologies that are consistent throughout the periods presented with consideration given to the potential impacts of the COVID-19 pandemic. However, actual results could differ materially from these estimates and be significantly affected by the severity and duration of the pandemic, the extent of actions to contain or treat COVID-19, including the effects of ongoing vaccination efforts, how quickly and to what extent normal economic and operating activity can resume, and the severity and duration of the global economic downturn that results from the pandemic.
Segment Information	Segment Information The Company manufactures, markets, and sells data storage devices and solutions in the U.S. and in foreign countries through its sales personnel, dealers, distributors, retailers, and subsidiaries. Historically, the Company has been managed and reported under a single operating segment. Late in the first quarter of fiscal 2021, the Chief Executive Officer, who is the Company’s Chief Operating Decision Maker, announced a decision to reorganize the Company’s business by forming two separate product business units: flash-based products and hard disk drives (“HDD”). To align with the new operating model and business structure, the Company is making management organizational changes and implementing new reporting modules and processes to provide discrete information to manage the business. Management expects to finalize its assessment of its operating segments when the implementations and transitions are completed, which is expected to be in the first quarter of fiscal 2022.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Accounting Pronouncements Recently Adopted In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Updates (“ASU”) No. 2016-13, “Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments” (“ASU 2016-13”). ASU 2016-13 seeks to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments, including trade receivables, and other commitments to extend credit held by a reporting entity at each reporting date. The amendments require an entity to replace the incurred loss impairment methodology in current U.S. GAAP with a methodology that reflects current expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. The amendments are effective for fiscal years (and interim periods within those fiscal years) beginning after December 15, 2019, which for the Company is the first quarter of fiscal 2021. The Company adopted this standard effective July 4, 2020 (the beginning of fiscal 2021) with no material impact on its Condensed Consolidated Financial Statements. In November 2018, the FASB issued ASU No. 2018-18, “Collaborative Arrangements (Topic 808): Clarifying the Interaction between Topic 808 and Topic 606” (“ASU 2018-18”). ASU 2018-18 clarifies that certain transactions between collaborative arrangement participants should be accounted for as revenue when the collaborative arrangement participant is a customer in the context of a unit of account and precludes recognizing as revenue consideration received from a collaborative arrangement participant if the participant is not a customer. This ASU requires retrospective adoption to the date the Company adopted Accounting Standards Codification (ASC) 606 by recognizing a cumulative-effect adjustment to the opening balance of retained earnings of the earliest annual period presented. The Company adopted this standard effective July 4, 2020 (the beginning of fiscal 2021) with no material impact on its Condensed Consolidated Financial Statements. Recently Issued Accounting Pronouncements Not Yet Adopted In December 2019, the FASB issued ASU No. 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes” (“ASU 2019-12”). ASU 2019-12 removes certain exceptions for recognizing deferred taxes for investments, performing intraperiod allocation and calculating income taxes in interim periods. The ASU also adds guidance to reduce complexity in certain areas, including recognizing deferred taxes for tax goodwill and allocating taxes to members of a consolidated group. This ASU is effective for fiscal years (and interim periods within those fiscal years) beginning after December 15, 2020, which for the Company is the first quarter of fiscal 2022. Early adoption is permitted. The Company does not expect this update to have a material impact on its Condensed Consolidated Financial Statements. In August 2020, the FASB issued ASU No. 2020-06, “Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity” (“ASU 2020-06”). ASU 2020-06 reduces the number of accounting models for convertible debt instruments and convertible preferred stock and results in fewer instruments with embedded conversion features being separately recognized from the host contract as compared with current standards. Those instruments that do not have a separately recognized embedded conversion feature will no longer recognize a debt issuance discount related to such a conversion feature and would recognize less interest expense on a periodic basis. Additionally, the ASU amends the calculation of the share dilution impact related to a conversion feature and eliminates the treasury method as an option. For instruments that do not have a component mandatorily settled in cash, the change will likely result in a higher amount of share dilution in the calculation of earnings per share. This ASU is effective for fiscal years (and interim periods within those fiscal years) beginning after December 15, 2021, which for the Company is the first quarter of fiscal 2023, with early adoption permitted beginning in the first quarter of fiscal 2022. The Company is currently assessing the impact and timing of adoption of this ASU.
Fair Value Measurements and Investments	Financial assets and liabilities that are remeasured and reported at fair value at each reporting period are classified and disclosed in one of the following three levels: Level 1. Quoted prices in active markets for identical assets or liabilities. Level 2. Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3. Inputs that are unobservable for the asset or liability and that are significant to the fair value of the assets or liabilities.

Organization and Basis of Presentation (Policies)

9 Months Ended

Apr. 02, 2021

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Western Digital Corporation (“Western Digital” or the “Company”) is a leading developer, manufacturer, and provider of data storage devices and solutions that address the evolving needs of the information technology (“IT”) industry and the infrastructure that enables the proliferation of data in virtually every other industry. The Company creates environments for data to thrive. The Company is driving the innovation needed to help customers capture, preserve, access and transform an ever-increasing diversity of data. Everywhere data lives, from advanced data centers to mobile sensors to personal devices, the Company’s industry-leading solutions deliver the possibilities of data.

The Company’s broad portfolio of technology and products address the following key end markets: Client Devices; Data Center Devices and Solutions; and Client Solutions. The Company also generates license and royalty revenue from its extensive intellectual property (“IP”), which is included in each of these three end market categories.

The accounting policies followed by the Company are set forth in Part II, Item 8, Note 1, Organization and Basis of Presentation, of the Notes to Consolidated Financial Statements included in the Company’s Annual Report on Form 10‑K for the fiscal year ended July 3, 2020. In the opinion of management, all adjustments necessary to fairly state the Condensed Consolidated Financial Statements have been made. All such adjustments are of a normal, recurring nature. Certain information and footnote disclosures normally included in the Consolidated Financial Statements prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). These Condensed Consolidated Financial Statements should be read in conjunction with the Consolidated Financial Statements and the notes thereto included in the Company’s Annual Report on Form 10‑K for the fiscal year ended July 3, 2020. The results of operations for interim periods are not necessarily indicative of results to be expected for the full year.

Fiscal Year

Fiscal YearThe Company’s fiscal year ends on the Friday nearest to June 30 and typically consists of 52 weeks. Approximately every five to six years, the Company reports a 53-week fiscal year to align the fiscal year with the foregoing policy. Fiscal year 2021, which ends on July 2, 2021, will be comprised of 52 weeks, with all quarters presented consisting of 13 weeks. Fiscal year 2020, which ended on July 3, 2020, was comprised of 53 weeks, with the first quarter consisting of 14 weeks and the remaining quarters consisting of 13 weeks each.

Use of Estimates

Company management has made estimates and assumptions relating to the reporting of certain assets and liabilities in conformity with U.S. GAAP. These estimates and assumptions have been applied using methodologies that are consistent throughout the periods presented with consideration given to the potential impacts of the COVID-19 pandemic. However, actual results could differ materially from these estimates and be significantly affected by the severity and duration of the pandemic, the extent of actions to contain or treat COVID-19, including the effects of ongoing vaccination efforts, how quickly and to what extent normal economic and operating activity can resume, and the severity and duration of the global economic downturn that results from the pandemic.

Segment Information

The Company manufactures, markets, and sells data storage devices and solutions in the U.S. and in foreign countries through its sales personnel, dealers, distributors, retailers, and subsidiaries. Historically, the Company has been managed and reported under a single operating segment. Late in the first quarter of fiscal 2021, the Chief Executive Officer, who is the Company’s Chief Operating Decision Maker, announced a decision to reorganize the Company’s business by forming two separate product business units: flash-based products and hard disk drives (“HDD”). To align with the new operating model and business structure, the Company is making management organizational changes and implementing new reporting modules and processes to provide discrete information to manage the business. Management expects to finalize its assessment of its operating segments when the implementations and transitions are completed, which is expected to be in the first quarter of fiscal 2022.

Recent Accounting Pronouncements

Accounting Pronouncements Recently Adopted

In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Updates (“ASU”) No. 2016-13, “Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments” (“ASU 2016-13”). ASU 2016-13 seeks to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments, including trade receivables, and other commitments to extend credit held by a reporting entity at each reporting date. The amendments require an entity to replace the incurred loss impairment methodology in current U.S. GAAP with a methodology that reflects current expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. The amendments are effective for fiscal years (and interim periods within those fiscal years) beginning after December 15, 2019, which for the Company is the first quarter of fiscal 2021. The Company adopted this standard effective July 4, 2020 (the beginning of fiscal 2021) with no material impact on its Condensed Consolidated Financial Statements.

In November 2018, the FASB issued ASU No. 2018-18, “Collaborative Arrangements (Topic 808): Clarifying the Interaction between Topic 808 and Topic 606” (“ASU 2018-18”). ASU 2018-18 clarifies that certain transactions between collaborative arrangement participants should be accounted for as revenue when the collaborative arrangement participant is a customer in the context of a unit of account and precludes recognizing as revenue consideration received from a collaborative arrangement participant if the participant is not a customer. This ASU requires retrospective adoption to the date the Company adopted Accounting Standards Codification (ASC) 606 by recognizing a cumulative-effect adjustment to the opening balance of retained earnings of the earliest annual period presented. The Company adopted this standard effective July 4, 2020 (the beginning of fiscal 2021) with no material impact on its Condensed Consolidated Financial Statements.

Recently Issued Accounting Pronouncements Not Yet Adopted

In December 2019, the FASB issued ASU No. 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes” (“ASU 2019-12”). ASU 2019-12 removes certain exceptions for recognizing deferred taxes for investments, performing intraperiod allocation and calculating income taxes in interim periods. The ASU also adds guidance to reduce complexity in certain areas, including recognizing deferred taxes for tax goodwill and allocating taxes to members of a consolidated group. This ASU is effective for fiscal years (and interim periods within those fiscal years) beginning after December 15, 2020, which for the Company is the first quarter of fiscal 2022. Early adoption is permitted. The Company does not expect this update to have a material impact on its Condensed Consolidated Financial Statements.

In August 2020, the FASB issued ASU No. 2020-06, “Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity” (“ASU 2020-06”). ASU 2020-06 reduces the number of accounting models for convertible debt instruments and convertible preferred stock and results in fewer instruments with embedded conversion features being separately recognized from the host contract as compared with current standards. Those instruments that do not have a separately recognized embedded conversion feature will no longer recognize a debt issuance discount related to such a conversion feature and would recognize less interest expense on a periodic basis. Additionally, the ASU amends the calculation of the share dilution impact related to a conversion feature and eliminates the treasury method as an option. For instruments that do not have a component mandatorily settled in cash, the change will likely result in a higher amount of share dilution in the calculation of earnings per share. This ASU is effective for fiscal years (and interim periods within those fiscal years) beginning after December 15, 2021, which for the Company is the first quarter of fiscal 2023, with early adoption permitted beginning in the first quarter of fiscal 2022. The Company is currently assessing the impact and timing of adoption of this ASU.

Fair Value Measurements and Investments

Financial assets and liabilities that are remeasured and reported at fair value at each reporting period are classified and disclosed in one of the following three levels:

Level 1. Quoted prices in active markets for identical assets or liabilities.

Level 2. Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

Level 3. Inputs that are unobservable for the asset or liability and that are significant to the fair value of the assets or liabilities.