Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jul. 31, 2020	Jul. 31, 2019	Jul. 31, 2020	Jul. 31, 2019
Income Tax Disclosure [Abstract]
Effective tax rates	8.90%	21.40%	16.00%	22.80%
Income tax provision included discrete tax benefit due to share-based payment transactions	$ 11,373	$ 210	$ 14,048	$ 3,227
Provisional discrete tax (benefit) expense				4,866
Total unrecognized tax benefits	443	$ 858	$ 443	$ 858
Increase in unrecognized tax benefits	$ 5,664

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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Amount of income tax expense (benefit) for remeasurement of deferred tax from change in tax rate pursuant to Tax Cuts and Jobs Act.

+ References

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-Publisher FASB
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Amount of unrecognized tax benefits.

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Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

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