Revenue from Contracts with Customers - Revenue Disaggregated by Geography (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jul. 31, 2018	Jul. 31, 2018
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	$ 6,012	$ 9,720
United States
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	1,124	1,252
Europe, Russia & CIS
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	2,747	4,766
Middle East & Africa
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	122	636
Asia-Pacific
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	1,979	2,679
Canada & Latin America
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	$ 40	$ 387