Quarterly report pursuant to Section 13 or 15(d)

Segment Information, Significant Customers and Geographic Information - Schedule of Revenue by Major Customers by Reporting Segments (Detail)

v3.10.0.1
Segment Information, Significant Customers and Geographic Information - Schedule of Revenue by Major Customers by Reporting Segments (Detail) - Customer Concentration Risk [Member] - Total Revenues [Member]
 3 Months Ended 9 Months Ended
Oct. 31, 2018
Oct. 31, 2017
Oct. 31, 2018
Oct. 31, 2017
Customer A [Member]        
Entity Wide Revenue Major Customer [Line Items]        
% of total revenues 10.00% 53.00% 15.00% 38.00%
Customer B [Member]        
Entity Wide Revenue Major Customer [Line Items]        
% of total revenues 13.00%      
Customer C [Member]        
Entity Wide Revenue Major Customer [Line Items]        
% of total revenues 12.00%      
Customer D [Member]        
Entity Wide Revenue Major Customer [Line Items]        
% of total revenues 10.00%