Subsequent Event - Additional Information (Detail) - USD ($) $ in Millions	Nov. 12, 2019	Oct. 31, 2020	Oct. 31, 2019
Minimum
Subsequent Event [Line Items]
Expected restructuring charges			$ 9.0
Minimum | Scenario Forecast
Subsequent Event [Line Items]
Expected restructuring charges		$ 9.0
Maximum
Subsequent Event [Line Items]
Expected restructuring charges			$ 12.0
Maximum | Scenario Forecast
Subsequent Event [Line Items]
Expected restructuring charges		$ 12.0
Subsequent Event
Subsequent Event [Line Items]
Restructuring and related activities, description	Pending final approval of our Board of Directors, customary regulatory approvals, and tax and legal considerations, this spin-off is expected to be completed in the second half of calendar 2020 and would create two independent publicly traded companies