Taxes - Provision for Income Taxes and Effective Tax Rates (Detail) - USD ($) $ in Thousands	3 Months Ended
	Jan. 31, 2018	Jan. 31, 2017
Income Tax Disclosure [Abstract]
Income before income taxes	$ 120,103	$ 108,361
Provision (benefit) for income taxes	$ 123,794	$ 21,773
Effective tax rate	103.10%	20.10%