Revenue from Contracts with Customers - Revenue Disaggregation (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Oct. 31, 2018	Oct. 31, 2018
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	$ 9,305	$ 19,025
Revenue recognized at a point in time
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	9,124	18,434
Revenue recognized over time
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	181	591
Seamap | Revenue recognized at a point in time
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	5,356	10,512
Seamap | Revenue recognized over time
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	181	591
Klein | Revenue recognized at a point in time
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	2,683	5,560
SAP | Revenue recognized at a point in time
Disaggregation of Revenue [Line Items]
Total revenue from contracts with customers	$ 1,085	$ 2,362