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Employee Benefit Plans - Stock Option Plans and Stock Purchase Rights Granted Under ESPP (Detail) - $ / shares | 12 Months Ended
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Oct. 31, 2020 | Oct. 31, 2019 | Oct. 31, 2018
Stock Option |  |  |
Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items] |  |  |
Expected life (in years) | 4 years 1 month 6 days | 4 years 1 month 6 days | 4 years 1 month 6 days
Risk-free interest rate, minimum | 0.26% | 1.28% | 2.10%
Risk-free interest rate, maximum | 1.71% | 2.73% | 2.95%
Volatility, minimum | 23.05% | 23.16% | 20.22%
Volatility, maximum | 32.80% | 24.76% | 21.04%
Weighted average estimated fair value (in USD per share) | $ 33.02 | $ 22.86 | $ 23.55
Employee Stock Purchase Plan |  |  |
Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items] |  |  |
Risk-free interest rate, minimum | 0.09% | 1.54% | 1.80%
Risk-free interest rate, maximum | 1.24% | 2.60% | 2.73%
Volatility, minimum | 25.59% | 23.73% | 19.99%
Volatility, maximum | 43.06% | 27.86% | 21.54%
Weighted average estimated fair value (in USD per share) | $ 47.69 | $ 35.18 | $ 23.34
Employee Stock Purchase Plan | Minimum |  |  |
Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items] |  |  |
Expected life (in years) | 6 months | 6 months | 6 months
Employee Stock Purchase Plan | Maximum |  |  |
Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items] |  |  |
Expected life (in years) | 2 years | 2 years | 2 years

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- Definition Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items] + References No definition available. + Details
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- Definition Share-based compensation arrangement by share-based payment award, fair value assumptions, weighted average estimated fair value + References No definition available. + Details
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- Definition The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References No definition available. + Details
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- Definition The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. + References No definition available. + Details
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- Definition The maximum risk-free interest rate assumption that is used in valuing an option on its own shares. + References No definition available. + Details
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- Definition The minimum risk-free interest rate assumption that is used in valuing an option on its own shares. + References No definition available. + Details
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- Definition Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2)(i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.D.2) -URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809 + Details
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