Income Taxes - Tax Loss and Credit Carryforwards Available to Offset Future Income Tax Liabilities (Detail) $ in Thousands	Oct. 31, 2017 USD ($)
Federal
Net Operating Loss and Tax Credit Carryforward [Line Items]
Net operating loss carryforward	$ 57,265
Credit carryforward	78,599
Federal foreign tax credit carryforward
Net Operating Loss and Tax Credit Carryforward [Line Items]
Credit carryforward	2,081
International foreign tax credit carryforward
Net Operating Loss and Tax Credit Carryforward [Line Items]
Credit carryforward	13,351
California research credit carryforward
Net Operating Loss and Tax Credit Carryforward [Line Items]
Credit carryforward	169,038
Other state research credit carryforward
Net Operating Loss and Tax Credit Carryforward [Line Items]
Credit carryforward	7,482
State net operating loss carryforward
Net Operating Loss and Tax Credit Carryforward [Line Items]
Net operating loss carryforward	$ 33,201