Quarterly report pursuant to Section 13 or 15(d)

Subsequent Event - Additional Information (Detail)

v3.19.3
Subsequent Event - Additional Information (Detail) - USD ($)
$ in Thousands
3 Months Ended
Nov. 04, 2019
Jan. 31, 2020
Oct. 31, 2019
Jan. 31, 2019
Subsequent Event [Line Items]        
Property and equipment, net     $ 6,577 $ 7,192
Buildings [Member]        
Subsequent Event [Line Items]        
Property and equipment, net     $ 5,900  
Subsequent Event [Member] | Acton, Massachusetts [Member]        
Subsequent Event [Line Items]        
Proceeds from sale of building $ 600      
Scenario Forecast [Member]        
Subsequent Event [Line Items]        
Recognized loss upon consummation of sale   $ 5,300