Employee Benefit Plans - Stock Option Plans and Stock Purchase Rights Granted Under ESPP (Detail) - $ / shares	12 Months Ended
Oct. 31, 2016	Oct. 31, 2015	Oct. 31, 2014
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 3 months 18 days	4 years 6 months
Risk-free interest rate, minimum	1.06%	1.24%	1.38%
Risk-free interest rate, maximum	1.63%	1.58%	1.74%
Volatility, minimum	19.21%	16.92%	18.38%
Volatility, maximum	21.62%	21.76%	20.00%
Weighted average estimated fair value	$ 8.97	$ 8.77	$ 10.95
Employee Stock Purchase Plan
Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items]
Risk-free interest rate, minimum	0.53%	0.12%	0.05%
Risk-free interest rate, maximum	0.86%	0.75%	0.58%
Volatility, minimum	17.03%	18.01%	16.84%
Volatility, maximum	25.46%	21.60%	18.78%
Weighted average estimated fair value	$ 12.75	$ 11.11	$ 9.17
Employee Stock Purchase Plan \| Minimum [Member]
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 [Member]
Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items]
Expected life (in years)	2 years	2 years	2 years

Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items]

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- Definition

Share-based compensation arrangement by share-based payment award, fair value assumptions, weighted average estimated fair value

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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.

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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.

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- Definition

The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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=27013229&loc=d3e301413-122809

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