Document and Entity Information - shares	3 Months Ended
	Jan. 31, 2016	Feb. 19, 2016
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jan. 31, 2016
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	Q1
Trading Symbol	SNPS
Entity Registrant Name	SYNOPSYS INC
Entity Central Index Key	0000883241
Current Fiscal Year End Date	--10-31
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		151,527,833