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Income Taxes - Additional Information (Detail) - USD ($) | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jul. 31, 2017 | Oct. 31, 2018 | Jul. 31, 2018 | Jan. 31, 2018 | Oct. 31, 2018 | Oct. 31, 2017 | Oct. 31, 2016
Taxes [Line Items] |  |  |  |  |  |  |
Integration of acquired technologies, tax recognition period |  |  |  |  | 5 years |  |
Blended tax rate |  |  |  |  | 23.40% |  |
Tax Cuts And Jobs Act Of 2017 provisional tax expense |  |  |  | $ 45,600,000 |  |  |
Tax Cuts And Jobs Act Of 2017 tax expense |  | $ 51,100,000 |  |  |  |  |
Tax Cuts And Jobs Act Of 2017 provisional transition tax expense |  |  | $ 73,400,000 |  |  |  |
Tax Cuts And Jobs Act Of 2017 provisional transition tax payable |  |  | $ 17,900,000 |  |  |  |
Tax Cuts And Jobs Act Of 2017, transition tax expense |  | 63,100,000 |  |  |  |  |
Tax Cuts And Jobs Act Of 2017, transition tax payable |  | 8,900,000 |  |  |  |  |
Deferred income tax expense |  | 172,000,000 |  |  | $ (210,310,000) | $ 123,052,000 | $ (14,037,000)
Provision (benefit) for income taxes |  |  |  |  | (68,975,000) | 246,535,000 | 62,722,000
Increase in valuation allowance |  |  |  |  | 79,500,000 |  |
Tax credits |  |  |  |  | 35,142,000 | 24,365,000 | 36,979,000
Increase in gross unrecognized tax benefits |  |  |  |  | 39,300,000 |  |
Gross unrecognized tax benefits |  | 131,019,000 |  |  | 131,019,000 | 91,637,000 | 106,542,000
Unrecognized tax benefits affecting effective tax rate |  | 120,900,000 |  |  | 120,900,000 | 88,500,000 |
The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations |  |  |  |  | 9,400,000 | 200,000 | 800,000
The amount of estimated penalties and interest accrued as of the balance sheet date arising from income tax examinations |  | 12,600,000 |  |  | 12,600,000 | 3,200,000 |
Decrease in unrecognized tax benefits resulting from settlement with taxing authorities |  |  |  |  | 175,000 | 784,000 |
Cash paid for income taxes during the year: |  |  |  |  | 252,522,000 | 103,478,000 | 69,447,000
Foreign Tax Authority |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Cash paid for income taxes during the year: |  | 67,700,000 |  |  |  |  |
Domestic Tax Authority |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Tax credits |  |  |  |  | 50,800,000 |  |
California Franchise Tax Board | fiscal year 2012 to 2014 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Increase in valuation allowance |  |  |  |  |  | 13,200,000 |
Decrease in unrecognized tax benefits resulting from settlement with taxing authorities |  |  |  |  |  | 14,600,000 |
Tax impact from tax settlements |  |  |  |  |  | 400,000 |
Decrease in deferred tax assets |  |  |  |  |  | 1,100,000 |
California Franchise Tax Board | fiscal year 2009 to 2011 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Increase in valuation allowance |  |  |  |  |  |  | 5,400,000
Decrease in unrecognized tax benefits resulting from settlement with taxing authorities |  |  |  |  |  |  | 10,300,000
Decrease in deferred tax assets |  |  |  |  |  |  | 4,900,000
Internal Revenue Service (IRS) | Fiscal Year 2017 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Decrease in unrecognized tax benefits resulting from settlement with taxing authorities |  |  |  |  | 21,800,000 |  |
Internal Revenue Service (IRS) | Fiscal Year 2016 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Decrease in unrecognized tax benefits resulting from settlement with taxing authorities |  |  |  |  |  | 4,600,000 |
Internal Revenue Service (IRS) | Fiscal Year 2015 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Decrease in unrecognized tax benefits resulting from settlement with taxing authorities |  |  |  |  |  |  | $ 20,700,000
Hungary | Fiscal Year 2011 to 2013 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Provision (benefit) for income taxes |  |  |  |  | 5,700,000 |  |
The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations | $ 18,000,000 |  |  |  |  |  |
Proposed tax assessment | $ 44,500,000 |  |  |  |  |  |
Remaining tax assessment amount |  |  |  |  | 36,200,000 |  |
KOREA, REPUBLIC OF | Fiscal years 2012 to 2016 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Tax impact from tax settlements |  |  |  |  | 7,900,000 |  |
Taiwan | Fiscal Year 2014 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Tax impact from tax settlements |  |  |  |  | 10,900,000 |  |
Taiwan | Fiscal Year 2011 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Decrease in unrecognized tax benefits resulting from settlement with taxing authorities |  |  |  |  |  | 700,000 |
Cash paid for income taxes during the year: |  |  |  |  |  | 300,000 |
INDIA | Fiscal 2010 to 2015 |  |  |  |  |  |  |
Taxes [Line Items] |  |  |  |  |  |  |
Tax impact from tax settlements |  |  |  |  |  | $ 4,600,000 |
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 |  | $ 7,000,000 |  |  | $ 7,000,000 |  |

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