v2.4.0.6

Employee Benefit Plans (Restricted Stock Units) (Details) (USD $)
In Thousands, except Per Share data, unless otherwise specified

3 Months Ended

12 Months Ended

0 Months Ended

Jan. 31, 2009

Restricted Stock Units (RSUs) [Member]

Oct. 31, 2011

Restricted Stock Units (RSUs) [Member]

years

Oct. 31, 2010

Restricted Stock Units (RSUs) [Member]

years

Oct. 31, 2009

Restricted Stock Units (RSUs) [Member]

years

Oct. 31, 2008

Restricted Stock Units (RSUs) [Member]

years

Mar. 24, 2011

2006 Employee Equity Incentive Plan [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Restricted Stock Units, Beginning balance

2,676

3,730

3,133

2,676

Restricted Stock Units, Granted

1,483

1,228

1,311

Restricted Stock Units, Assumed

713

^[1]

Restricted Stock Units, Vested

(1,522)

^[2],[3]

(1,221)

^[2],[3]

(787)

^[2],[3]

Restricted Stock Units, Forfeited

(237)

(123)

(67)

Restricted Stock Units, Ending balance

3,454

3,730

3,133

2,676

Weighted Average Grant Date Fair Value, Beginning balance

$ 25.45

$ 22.71

$ 22.63

$ 25.45

Weighted Average Grant Date Fair Value, Granted

$ 26.89

$ 22.00

$ 18.78

Weighted Average Grant Date Fair Value, Assumed

$ 23.69

^[1]

Weighted Average Grant Date Fair Value, Vested

$ 23.11

^[2],[3]

$ 22.40

^[2],[3]

$ 25.64

^[2],[3]

Weighted Average Grant Date Fair Value, Forfeited

$ 23.49

$ 22.51

$ 24.64

Weighted Average Grant Date Fair Value

$ 24.28

$ 22.71

$ 22.63

$ 25.45

Weighted Average Remaining Contractual Life (In Years)

1.48

1.41

1.41

1.61

Aggregate Fair Value, Vested

$ 35,164

^[2],[3]

$ 27,345

^[2],[3]

$ 14,859

^[2],[3]

Share reserve ratio

1.36

2.18

Revised share reserve ratio

1.25

Vesting period, minimum (in years)

three

Vesting period, maximum (in years)

four

[1]	The Company assumed restricted stock units outstanding under various plans through acquisitions.
[2]	Represents the market value of Synopsys common stock on the date the restricted stock unit vests.
[3]	The number of vested restricted stock units includes shares that were withheld on behalf of employees to satisfy the statutory tax withholding requirements.

X

- Definition

Revised share reserve ratio

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- Definition

Share based compensation arrangement by share based payment award, equity instruments other than options, assumed in period

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- Definition

The maximum vesting term over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition.

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The minimum vesting term over which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

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-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.



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- Definition

The weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect during the reporting period as a result of the occurrence of a terminating event specified in the contractual agreement of the plan.

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

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-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.



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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

-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.



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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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

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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph A240

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-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.



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-Paragraph A240

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-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.



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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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-Publisher FASB

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-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.



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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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-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.



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The weighted average period between the balance sheet date and expiration for equity-based awards other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan), which may be expressed in a decimal value for number of years.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

The total fair value of equity-based awards for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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