Summary of Significant Accounting Policies - Changes in Allowance for Doubtful Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2015
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance at Beginning of Period	$ 3,201	$ 2,561	$ 2,026
Provisions	2,149	950	1,300
Write-offs	(185)	(310)	(765)
Balance at End of Period	$ 5,165	$ 3,201	$ 2,561