Financial Assets And Liabilities - Additional Information (Detail)	12 Months Ended
Oct. 31, 2012
Financial Assets and Liabilities [Line Items]
Shipments period using hedges (in months)	one
Minimum forward contracts terms (in months)	One
Forward contracts terms (in months)	21
Percentage of expected hedge balance to be reclassed out of OCI	40.00%
Period for % of hedge balance in OCI to be reclassified to statement of operations (in months)	12 months
Foreign Exchange Contracts \| Maximum
Financial Assets and Liabilities [Line Items]
Duration of foreign exchange forward contracts	1 year
Cash Flow Hedging \| Maximum
Financial Assets and Liabilities [Line Items]
Derivative maturity period (in months)	21
Derivative maturity period of rolled over currency contracts (in years)	3
Non-Designated Hedging Instrument
Financial Assets and Liabilities [Line Items]
Forward contracts terms (in months)	One

Derivative Maturity Period (in months).

No definition available.

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Namespace Prefix:	snps_
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Period Type:	duration

- Definition

Derivative Maturity Period of Roll Over Currency Contract.

+ References

No definition available.

+ Details

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- Details

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- Definition

Minimum Length of Time Hedged in Foreign Currency Cash Flow Hedge

+ References

No definition available.

+ Details

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- Definition

Percentage of hedge balance to be reclassed out of OCI to statement of operations in the next 12 months

+ References

No definition available.

+ Details

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- Definition

High end period remaining until maturity for the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Estimated period for the anticipated transfer of gain (loss), net, from accumulated other comprehensive income into earnings, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Description of the reasons for holding or issuing foreign currency exchange rate derivative instruments. Includes discussion of the objectives for holding the instruments, the context needed to understand those objectives, and the strategies for achieving those objectives. Disclosures may be more meaningful if such objectives and strategies are described in the context of an entity's overall risk management profile.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 44

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579245-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5579240-113959

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=7476318&loc=d3e41641-113959

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- Definition

Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7668309&loc=d3e80748-113994

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(3)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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