Document and Entity Information	9 Months Ended
	Dec. 31, 2012	Jan. 24, 2013
Document and Entity Information [Abstract]
Entity Registrant Name	IXYS CORP /DE/
Entity Central Index Key	0000945699
Document Type	10-Q
Document Period End Date	Dec. 31, 2012
Amendment Flag	false
Current Fiscal Year End Date	--03-31
Entity Well Known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Accelerated Filer
Entity Common Stock Shares Outstanding		30,841,192
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q3