Document and Entity Information (USD $)	12 Months Ended
	Mar. 31, 2013	May 15, 2013	Sep. 28, 2012
Entity Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Mar. 31, 2013
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	FY
Trading Symbol	QLGC
Entity Registrant Name	QLOGIC CORP
Entity Central Index Key	0000918386
Current Fiscal Year End Date	--03-31
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		89,042,000
Entity Public Float			$ 1,054,375,000