Effective Income Tax Rate Reconciliation, Tax Settlement and Tax Credit, Foreign, Amount

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- Definition

Taxes [Line Items]

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- Definition

Unrecognized Tax Benefits, Income Tax Expense

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

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- Definition

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

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-Topic 235
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The amount of the additional liability or refund received or expected based on a final settlement with a taxing authority.

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- Definition

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

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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
	Jul. 31, 2023	Jul. 31, 2023	Oct. 31, 2019	Oct. 31, 2017	May 17, 2023
Taxes [Line Items]
Statutory federal income tax rate		21.00%
Minimum
Taxes [Line Items]
Estimated potential decrease in underlying unrecognized tax benefits	$ 0.0	$ 0.0
Maximum
Taxes [Line Items]
Estimated potential decrease in underlying unrecognized tax benefits	10.0	$ 10.0
Synopsys Hungary \| Foreign Tax Authority \| Tax Year 2011 - Tax Year 2013 \| Hungarian Tax Authority
Taxes [Line Items]
Aggregate tax assessment (refund)				$ 25.0	$ (39.1)
Estimate of additional penalties and interest				$ 11.0
Unrecognized tax benefits			$ 17.4
Release of unrecognized tax benefit and offsetting foreign tax credits, net benefit	$ 23.8