Quarterly report pursuant to Section 13 or 15(d)

Segment Information, Significant Customers and Geographic Information - Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area (Parenthetical) (Detail)

v3.19.3
Segment Information, Significant Customers and Geographic Information - Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area (Parenthetical) (Detail) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Oct. 31, 2019
Oct. 31, 2018
Oct. 31, 2019
Jul. 31, 2019
Oct. 31, 2018
Jul. 31, 2018
Segment Reporting Information [Line Items]            
Total revenues $ 20,544 $ 18,611 $ 47,841   $ 45,447  
United States Revenue [Member]            
Segment Reporting Information [Line Items]            
Total revenues $ 10,425 $ 8,124   $ 23,489   $ 19,013
Total Revenues [Member] | Customer Concentration Risk [Member] | United States Revenue [Member]            
Segment Reporting Information [Line Items]            
% of total revenue 51.00% 44.00%   49.00%   42.00%