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Income Taxes - Additional Information (Detail) - USD ($) | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jul. 31, 2017 | Jul. 31, 2019 | Oct. 31, 2020 | Oct. 31, 2019 | Oct. 31, 2018 | Apr. 30, 2019 | Oct. 31, 2017
Taxes [Line Items] |  |  |  |  |  |  |
Federal statutory income tax rate, percent |  |  | 21.00% |  |  |  |
Undistributed earnings of foreign subsidiaries |  |  | $ 0 | $ (6,341,000) | $ 974,000 |  |
Tax Cuts And Jobs Act Of 2017, transition tax expense |  |  |  | 17,900,000 | 63,100,000 |  |
Increase in valuation allowance |  |  | 1,600,000 |  |  |  |
Tax credits |  |  | 39,206,000 | 34,485,000 | 35,142,000 |  |
Decrease in gross unrecognized tax benefits |  |  | 33,100,000 |  |  |  |
Gross unrecognized tax benefits |  |  | 83,149,000 | 116,212,000 | 131,019,000 |  |
Unrecognized tax benefits affecting effective tax rate |  |  | 83,100,000 | 116,200,000 |  |  |
The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations |  |  | 200,000 | 300,000 | 9,400,000 |  |
The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations |  |  | 13,100,000 | 12,800,000 |  |  |
Cumulative effect of new accounting principle in period of adoption |  |  | 4,912,367,000 | 4,088,876,000 | 3,485,015,000 |  | $ 3,279,724,000
Decrease in unrecognized tax benefits resulting from settlement with taxing authorities |  |  | 1,411,000 | 1,624,000 |  |  |
California Franchise Tax Board | Fiscal Year 2015 to 2017 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Increase in valuation allowance |  |  | 20,200,000 |  |  |  |
Decrease in unrecognized tax benefits resulting from settlement with taxing authorities |  |  | 20,200,000 |  |  |  |
Internal Revenue Service (IRS) | Fiscal Year 2019 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Decrease in unrecognized tax benefits resulting from settlement with taxing authorities |  |  | 6,300,000 |  |  |  |
Internal Revenue Service (IRS) | Fiscal Year 2018 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Decrease in unrecognized tax benefits resulting from settlement with taxing authorities |  |  |  | 5,400,000 |  |  |
Foreign tax credits, resulting from settlements with taxing authorities |  |  |  | 28,100,000 |  |  |
Internal Revenue Service (IRS) | Fiscal Year 2017 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Decrease in unrecognized tax benefits resulting from settlement with taxing authorities |  |  |  |  | 21,800,000 |  |
Hungary | Fiscal Year 2011 to 2013 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Gross unrecognized tax benefits |  |  |  |  |  | $ 17,400,000 |
The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations | $ 11,000,000.0 |  |  |  |  |  |
Proposed tax assessment | $ 25,000,000.0 |  |  |  |  |  |
Hungary | Fiscal Year 2014 To 2018 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Decrease in unrecognized tax benefits resulting from settlement with taxing authorities |  |  | 6,900,000 |  |  |  |
Tax impact from tax settlements |  |  | 1,400,000 |  |  |  |
Taiwan | Fiscal Year 2017 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Tax impact from tax settlements |  |  |  | 5,500,000 |  |  |
Minimum |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Estimated potential decrease in underlying unrecognized tax benefits, minimum |  |  | 0.0 |  |  |  |
Maximum |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Estimated potential decrease in underlying unrecognized tax benefits, minimum |  |  | 42,500,000 |  |  |  |
Retained Earnings |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Cumulative effect of new accounting principle in period of adoption |  |  | $ 3,795,397,000 | 3,164,144,000 | $ 2,543,688,000 |  | $ 2,143,873,000
Altera |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Income tax expense, resulting from legal settlement |  | $ 18,300,000 |  |  |  |  |
Cumulative effect, period of adoption, adjustment | Accounting Standards Update 2016-16 | Retained Earnings |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Cumulative effect of new accounting principle in period of adoption |  |  |  | $ 130,500,000 |  |  |

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