Document and Entity Information	6 Months Ended
Apr. 30, 2011	May 23, 2011
Document and Entity Information
Document Type	10-Q
Amendment Flag	true
Document Period End Date	Apr. 30, 2011
Entity Registrant Name	SYNOPSYS INC
Entity Central Index Key	0000883241
Document Fiscal Year Focus	2011
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--10-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		146,679,418
Trading Symbol	SNPS
Amendment Description	Synopsys, Inc. is filing this Amendment No. 1 to its Quarterly Report on Form 10-Q for the fiscal quarter ended April 30, 2011 ("Form 10-Q"), which was filed with the Securities and Exchange Commission on May 27, 2011, for the sole purpose of furnishing corrected XBRL Interactive Data Files. Due to a filing error by a third party financial printer, the XBRL Interactive Data Files originally furnished with the Form 10-Q contained inaccuracies. No other changes have been made to the Form 10-Q. Except as specifically described above, this Amendment No. 1 does not reflect events occurring after the filing of the Form 10-Q, does not update disclosures contained in the Form 10-Q and does not modify or amend the Form 10-Q.

Description of changes contained within amended document.

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