v2.4.0.6

Commitments And Contingencies (Narrative) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended |
--- | --- | ---
Oct. 31, 2011 | Oct. 31, 2010 | Oct. 31, 2009 | Oct. 15, 2011 sqft
Commitments And Contingencies [Abstract] |  |  |  |
Rent expenses | $ 58.1 | $ 49.7 | $ 45.2 |
Number of buildings to be leased |  |  |  | 2
Total square feet of buildings |  |  |  | 341,000
Total square feet of buildings after enlargement |  |  |  | 440,000
Lease initiation date |  |  |  | March 1, 2015
Lease expiration period, (in years) |  |  |  | 15
Extended lease term, years |  |  |  | 19

X
- Definition Extended lease term. + References No definition available. + Details
Name: | snps_ExtendedLeaseTerm
Namespace Prefix: | snps_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Lease expiration period + References No definition available. + Details
Name: | snps_LeaseExpirationPeriod
Namespace Prefix: | snps_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Lease initiation date. + References No definition available. + Details
Name: | snps_LeaseInitiationDate
Namespace Prefix: | snps_
Data Type: | invest:dateStringItemType
Balance Type: | na
Period Type: | instant

X
- Definition Square feet of buildings after enlargement + References No definition available. + Details
Name: | snps_SquareFeetOfBuildingsAfterEnlargement
Namespace Prefix: | snps_
Data Type: | num:areaItemType
Balance Type: | na
Period Type: | instant

X
- Definition Total square feet of buildings after enlargement. + References No definition available. + Details
Name: | snps_TotalSquareFeetOfBuildingsAfterEnlargement
Namespace Prefix: | snps_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

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

X
- Definition Rental expense incurred for leased assets including furniture and equipment which has not been recognized in costs and expenses applicable to sales and revenues; for example, cost of goods sold or other operating costs and expenses. + References No definition available. + Details
Name: | us-gaap_LeaseAndRentalExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The number of units (items of property) under operating lease arrangements. + References No definition available. + Details
Name: | us-gaap_PropertySubjectToOrAvailableForOperatingLeaseNumberOfUnits
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant