Effective Income Tax Rate Reconciliation, Share-based Compensation, Excess Tax Benefit, Amount

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Taxes [Line Items]

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount of decrease reasonably possible in the next twelve months for the unrecognized tax benefit.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards classified as noncurrent.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Estimated amount of loss resulting from an adverse tax position.

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The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

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The increase (decrease) during the reporting period in the account that represents the temporary difference that results from Income or Loss that is recognized for accounting purposes but not for tax purposes and vice versa.

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Amount of unrecognized tax benefits.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Taxes - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended
Taxes - Additional Information (Detail) - USD ($)	Oct. 31, 2016	Jan. 31, 2017	Jan. 31, 2016	Nov. 01, 2016
Taxes [Line Items]
Statutory federal income tax rate		35.00%
Gross unrecognized tax benefits		$ 104,300,000
Unrecognized tax benefits that would affect effective tax rate		99,600,000
Long-term deferred income taxes	$ 281,926,000	355,469,000
Share-based compensation, excess tax benefit, amount		3,000,000
Fiscal year 2011, 2010, and 2009 \| California Franchise Tax Board
Taxes [Line Items]
Reduction in deferred tax asset due to tax settlement			$ 4,900,000
Unrecognized tax benefits decrease resulting from settlement			10,300,000
Deferred tax asset, increase (decrease), amount			$ 5,400,000
Minimum
Taxes [Line Items]
Estimated potential decrease in underlying unrecognized tax benefits		0
Maximum
Taxes [Line Items]
Estimated potential decrease in underlying unrecognized tax benefits		$ 12,000,000
Accounting Standards Update 2016-09 \| New Accounting Pronouncement, Early Adoption, Effect
Taxes [Line Items]
Long-term deferred income taxes				$ 106,500,000
Retained Earnings \| Accounting Standards Update 2016-09 \| New Accounting Pronouncement, Early Adoption, Effect
Taxes [Line Items]
Cumulative effect adjustment				$ 106,500,000
Synopsys Hungary \| Foreign Tax Authority \| Tax Year 2011 - Tax Year 2013 \| Hungarian Tax Authority
Taxes [Line Items]
Estimate of tax assessment	46,000,000
Estimate of additional penalties and interest	$ 19,000,000