v2.4.0.6

Summary of Intangible Assets (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Oct. 31, 2012
Finite-Lived Intangible Assets [Line Items] |
Acquisition of additional intangible assets | $ 370.7

X
- Definition Acquisition of additional intangible assets. + References No definition available. + Details
Name: | snps_AcquisitionOfAdditionalIntangibleAssets
Namespace Prefix: | snps_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_FiniteLivedIntangibleAssetsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration