XML 95 R79.htm IDEA: XBRL DOCUMENT v3.3.1.900
Concentrations - Additional Information (Detail)
$ in Millions
12 Months Ended
Jan. 31, 2016
USD ($)
Customer
Supplier
Jan. 31, 2015
USD ($)
Customer
Risks Inherent in Servicing Assets and Servicing Liabilities [Line Items]    
Minimum rate of consolidated accounts receivable 10.00% 10.00%
Foreign bank deposits $ 3.1  
Number of suppliers manufacture land based seismic systems and equipment in use | Supplier 2  
Credit Risk [Member]    
Risks Inherent in Servicing Assets and Servicing Liabilities [Line Items]    
Concentration risk number of customer | Customer 4 3
Aggregate amount of accounts receivable from customers $ 11.6 $ 11.3