Document and Entity Information	9 Months Ended
	Apr. 03, 2015	May 06, 2015
Document Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Apr. 03, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q3
Trading Symbol	WDC
Entity Registrant Name	WESTERN DIGITAL CORP
Entity Central Index Key	0000106040
Current Fiscal Year End Date	--07-03
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		230,912,060