Business Combinations - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
Jul. 31, 2021	Oct. 31, 2020
Business Acquisition [Line Items]
Consideration transfered	$ 166,900
Goodwill	3,485,181	$ 3,365,114
Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Identifiable intangibles assets acquired	57,700
Goodwill	114,600
Series of Individually Immaterial Business Acquisitions \| Semiconductor & System Design:
Business Acquisition [Line Items]
Goodwill	68,900
Series of Individually Immaterial Business Acquisitions \| Software Integrity:
Business Acquisition [Line Items]
Goodwill	$ 45,700

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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