Annual report pursuant to Section 13 and 15(d)

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

v3.7.0.1
Segment Information, Significant Customers and Geographic Information - Schedule of Revenue by Major Customers by Reporting Segments (Detail) - Customer Concentration Risk [Member] - Total Revenue [Member]
12 Months Ended
Jan. 31, 2017
Jan. 31, 2016
Jan. 31, 2015
Revenue, Major Customer [Line Items]      
% of total revenues 10.00% 10.00% 10.00%
Customer A [Member]      
Revenue, Major Customer [Line Items]      
% of total revenues 30.00% 28.00% 17.00%
Customer B [Member]      
Revenue, Major Customer [Line Items]      
% of total revenues   10.00% 17.00%