v2.4.0.6

Stock Option Plans and Stock Purchase Rights Granted Under ESPP (Detail) (USD $) | 12 Months Ended
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Oct. 31, 2012 | Oct. 31, 2011 | Oct. 31, 2010
Stock Option |  |  |
Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items] |  |  |
Risk-free interest rate, minimum | 0.22% | 0.96% | 1.08%
Risk-free interest rate, maximum | 0.95% | 2.28% | 2.57%
Volatility, minimum | 22.65% | 26.96% | 26.92%
Volatility, maximum | 29.76% | 30.30% | 30.76%
Weighted average estimated fair value | $ 8.46 | $ 7.04 | $ 7.10
Stock Option | Minimum |  |  |
Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items] |  |  |
Expected life (in years) | 1 year | 4 years 9 months 18 days | 3 years 7 months 24 days
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 |  | 5 years 8 months 23 days
Employee Stock Purchase Plan |  |  |
Schedule of Weighted Average Assumptions for Fair Values of Stock Options[Line Items] |  |  |
Risk-free interest rate, minimum | 0.16% | 0.09% | 0.18%
Risk-free interest rate, maximum | 0.34% | 0.68% | 0.78%
Volatility, minimum | 21.95% | 19.48% | 22.40%
Volatility, maximum | 23.20% | 27.08% | 31.27%
Weighted average estimated fair value | $ 8.02 | $ 6.82 | $ 6.16
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 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 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=6793087&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 + 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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