Stock Option Plans and Stock Purchase Rights Granted Under ESPP (Detail) (USD $)	12 Months Ended
	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