Assets And Liabilities Measured At Fair Value On Recurring Basis (Detail) (Fair Value, Measurements, Recurring, USD $) In Thousands, unless otherwise specified	Jul. 31, 2012		Oct. 31, 2011
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	$ 720,600		$ 784,988
Total liabilities	16,982		21,152
Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	719,242		633,830
Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	1,358		151,158
Total liabilities	15,628		16,856
Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total liabilities	1,354		4,296
Money Market Funds (U.S.)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	621,553		543,770
Money Market Funds (U.S.) | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	621,553		543,770
Municipal securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term investments			148,997
Municipal securities | Significant Other Observable Inputs (Level 2)
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	1,358		2,161
Accounts payable and accrued liabilities	15,628		16,856
Foreign Currency Derivative Contracts | Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Prepaid and other current assets	1,358		2,161
Accounts payable and accrued liabilities	15,628		16,856
Deferred Compensation Plan Assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other long-term assets	97,689		90,060
Deferred Compensation Plan Assets | Quoted Prices In Active Markets For Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Other long-term assets	97,689		90,060
Contingent Consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accounts payable and accrued liabilities	999	[1]	2,096
Other long-term liabilities	355	[1]	2,200
Contingent Consideration | Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accounts payable and accrued liabilities	999	[1]	2,096
Other long-term liabilities	$ 355	[1]	$ 2,200

[1] Includes addition of contingent consideration of $0.7 million arising from a business combination completed during fiscal 2012 which is payable over two years.