v3.6.0.2
Document and Entity Information - shares
6 Months Ended
Dec. 30, 2016
Feb. 03, 2017
Document Information [Line Items]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Dec. 30, 2016  
Document Fiscal Year Focus 2017  
Document Fiscal Period Focus Q2  
Entity Registrant Name WESTERN DIGITAL CORP  
Entity Central Index Key 0000106040  
Current Fiscal Year End Date --06-30  
Entity Well-known Seasoned Issuer Yes  
Entity Current Reporting Status Yes  
Entity Voluntary Filers No  
Entity Filer Category Large Accelerated Filer  
Entity Common Stock, Shares Outstanding   288,070,433