Employee Benefit Plans - Stock Option Plans and Stock Purchase Rights Granted Under ESPP (Detail) (USD $)	12 Months Ended
Oct. 31, 2014	Oct. 31, 2013	Oct. 31, 2012
Stock Option
Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items]
Expected life (in years)	4 years 6 months	4 years 8 months 12 days
Risk-free interest rate, minimum	1.38%	0.62%	0.22%
Risk-free interest rate, maximum	1.74%	1.66%	0.95%
Volatility, minimum	18.38%	20.61%	22.65%
Volatility, maximum	20.00%	26.47%	29.76%
Weighted average estimated fair value	$ 10.95	$ 7.29	$ 8.46
Stock Option \| Minimum
Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items]
Expected life (in years)			1 year
Stock Option \| Maximum
Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items]
Expected life (in years)			4 years 10 months 24 days
Employee Stock Purchase Plan
Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items]
Risk-free interest rate, minimum	0.05%	0.10%	0.16%
Risk-free interest rate, maximum	0.58%	0.43%	0.34%
Volatility, minimum	16.84%	17.12%	21.95%
Volatility, maximum	18.78%	21.75%	23.20%
Weighted average estimated fair value	$ 9.17	$ 8.19	$ 8.02
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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Share-based compensation arrangement by share-based payment award, fair value assumptions, weighted average estimated fair value

+ References

No definition available.

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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 S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.D.2)

-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

Reference 2: 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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section D

-Subsection 2

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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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No definition available.

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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.

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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.

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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.

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