Employee Benefit Plans (Employee Stock Purchase Plan) - Additional Information (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended
	Oct. 31, 2012 Y	Oct. 31, 2011	Oct. 31, 2010	Apr. 03, 2012
Employee Stock Purchase Plan [Line Items]
Threshold for employee stock purchases under ESPP, maximum value	85.00%
ESPP offering period (in years)	2
Increase in number of shares authorized for issuance under plan				5.0
Shares issued	2.0	2.2	2.5
Weighted average purchase price of stock purchased	$ 21.65	$ 17.95	$ 15.32
Shares reserved for future issuance under the ESPP	5.9