Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (Fair Value, Measurements, Recurring, USD $) In Thousands, unless otherwise specified	Oct. 31, 2012	Oct. 31, 2011
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	$ 345,632	$ 784,988
Total liabilities	5,651	21,152
Money Market Funds (U.S.)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	239,770	543,770
Municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments		148,997
Foreign Currency Derivative Contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Prepaid and other current assets	5,217	2,161
Accounts payable and accrued liabilities	4,827	16,856
Deferred Compensation Plan Assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other long-term assets	100,645	90,060
Contingent Consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accounts payable and accrued liabilities	469	2,096
Other long-term liabilities	355	2,200
Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	340,415	633,830
Quoted Prices In Active Markets For Identical Assets (Level 1) | Money Market Funds (U.S.)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	239,770	543,770
Quoted Prices In Active Markets For Identical Assets (Level 1) | Deferred Compensation Plan Assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other long-term assets	100,645	90,060
Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	5,217	151,158
Total liabilities	4,827	16,856
Significant Other Observable Inputs (Level 2) | Municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments		148,997
Significant Other Observable Inputs (Level 2) | Foreign Currency Derivative Contracts
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Prepaid and other current assets	5,217	2,161
Accounts payable and accrued liabilities	4,827	16,856
Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total liabilities	824	4,296
Significant Unobservable Inputs (Level 3) | Contingent Consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accounts payable and accrued liabilities	469	2,096
Other long-term liabilities	$ 355	$ 2,200