Goodwill and Intangible Assets - Estimated Future Amortization of Intangible Assets (Parenthetical) (Detail)	12 Months Ended
Oct. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Estimated completion period of IPR&D projects, years	1 year

Estimated completion period of in process research and development projects.

No definition available.

Name:	snps_EstimatedCompletionPeriodOfInProcessResearchAndDevelopmentProjects
Namespace Prefix:	snps_
Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration