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Segment Disclosure - Additional information (Detail)
3 Months Ended 6 Months Ended
Apr. 30, 2020
Customer
Apr. 30, 2019
Customer
Apr. 30, 2020
Customer
Segment
Apr. 30, 2019
Customer
Segment Reporting Information [Line Items]        
Number of reportable operating segment | Segment     2  
Customer concentration risk | Sales revenue        
Segment Reporting Information [Line Items]        
Number of major customers | Customer 1 1 1 1