Income Taxes (Narrative) (Details) (USD $)	0 Months Ended	3 Months Ended	12 Months Ended
	May 31, 2012	Apr. 30, 2011	Oct. 31, 2012	Oct. 31, 2011	Oct. 31, 2010	Jan. 19, 2012
Operating Loss Carryforwards [Line Items]
Effective tax rate (ETR)			9.70%	9.00%
Loss on repurchase of notes		$ 16,500,000		$ 16,500,000
Write-off debt issuance costs in interest expense	1,400,000	4,400,000
Redemption premium related to notes		12,100,000		12,100,000
Statutory income tax rate			35.00%
Current deferred tax liabilities			300,000	300,000
Valuation allowance			1,107,000	0
Undistributed earnings of its foreign subsidiaries			1,100,000,000
Research credits			131,000	1,183,000	525,000
Changes in unrecognized tax benefits			5,300,000
Unrecognized tax benefits that would impact ETR			29,500,000
Interest and penalties			2,600,000
Unrecognized tax benefits related to tax positions			5,000,000
Income tax, agreed net deficiency						50,000
Federal [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards			2,700,000
Federal net operating loss carryforwards related to share option exercises			7,900,000
Alternative minimum tax credits			6,500,000
Research credits			2,000,000
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards			34,600,000
California [Member]
Operating Loss Carryforwards [Line Items]
Research credits			300,000
Senior Notes [Member]
Operating Loss Carryforwards [Line Items]
Write-off debt issuance costs in interest expense				$ 4,400,000