v3.7.0.1
Document and Entity Information - shares
9 Months Ended
Mar. 31, 2017
May 03, 2017
Document Information [Line Items]    
Entity Registrant Name WESTERN DIGITAL CORP  
Entity Central Index Key 0000106040  
Current Fiscal Year End Date --06-30  
Entity Filer Category Large Accelerated Filer  
Document Type 10-Q  
Document Period End Date Mar. 31, 2017  
Document Fiscal Year Focus 2017  
Document Fiscal Period Focus Q3  
Amendment Flag false  
Entity Common Stock, Shares Outstanding   291,242,394
Entity Well-known Seasoned Issuer Yes  
Entity Voluntary Filers No  
Entity Current Reporting Status Yes