Financial Assets And Liabilities (Summary Of Cash, Cash Equivalents And Investments) (Details) (USD $) In Thousands, unless otherwise specified	Jan. 31, 2012		Oct. 31, 2011
Financial Assets And Liabilities [Line Items]
Cost	$ 947,176		$ 1,007,909
Gross Unrealized Gains	330		296
Gross Unrealized Losses Less Than 12 Months	(35)		(149)
Gross Unrealized Losses 12 Months or Longer
Estimated Fair Value	947,471	[1]	1,008,056	[1]
Classified As Current Assets Total [Member]
Financial Assets And Liabilities [Line Items]
Cost	943,194		1,003,927
Gross Unrealized Gains	330		296
Gross Unrealized Losses Less Than 12 Months	(35)		(149)
Gross Unrealized Losses 12 Months or Longer
Estimated Fair Value	943,489	[1]	1,004,074	[1]
Non-Interest Bearing Cash (U.S. And International) [Member]
Financial Assets And Liabilities [Line Items]
Cost	164,802		149,998
Gross Unrealized Losses 12 Months or Longer
Estimated Fair Value	164,802	[1]	149,998	[1]
Money Market Funds (U.S.) [Member]
Financial Assets And Liabilities [Line Items]
Cost	27,662		55,267
Gross Unrealized Losses 12 Months or Longer
Estimated Fair Value	27,662	[1]	55,267	[1]
Cash Deposits And Money Market Funds (International) [Member]
Financial Assets And Liabilities [Line Items]
Cost	618,875		649,812
Gross Unrealized Losses 12 Months or Longer
Estimated Fair Value	618,875	[1]	649,812	[1]
Strategic Investments [Member]
Financial Assets And Liabilities [Line Items]
Cost	3,982		3,982
Gross Unrealized Losses 12 Months or Longer
Estimated Fair Value	3,982	[1]	3,982	[1]
Municipal Securities [Member]
Financial Assets And Liabilities [Line Items]
Cost	131,855		148,850
Gross Unrealized Gains	330		296
Gross Unrealized Losses Less Than 12 Months	(35)		(149)
Gross Unrealized Losses 12 Months or Longer
Estimated Fair Value	$ 132,150	[1]	$ 148,997	[1]

[1] See Note 4 for further discussion of fair values.