XML 73 R46.htm IDEA: XBRL DOCUMENT v3.20.1
Goodwill and Intangible Assets - Additional Information (Detail) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Apr. 30, 2020
Apr. 30, 2019
Apr. 30, 2020
Apr. 30, 2019
Goodwill And Intangible Assets Disclosure [Abstract]        
Amortization expense $ 3.4 $ 4.6 $ 7.4 $ 9.3