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Leases - Additional Information (Detail) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Jan. 31, 2015
Jan. 31, 2014
Jan. 31, 2013
Foreign Country [Member]      
Property, Plant and Equipment [Line Items]      
Office rental expense $ 1,400us-gaap_OperatingLeasesRentExpenseNet
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_ForeignCountryMember
$ 1,400us-gaap_OperatingLeasesRentExpenseNet
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_ForeignCountryMember
$ 1,500us-gaap_OperatingLeasesRentExpenseNet
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_ForeignCountryMember
Seismic Equipment Lease Pool [Member] | Domestic Tax Authority [Member]      
Property, Plant and Equipment [Line Items]      
Lease expense incurred by the Company $ 1,400us-gaap_LeaseOperatingExpense
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_LeaseholdImprovementsMember
$ 621us-gaap_LeaseOperatingExpense
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_LeaseholdImprovementsMember
$ 1,800us-gaap_LeaseOperatingExpense
/ us-gaap_IncomeTaxAuthorityAxis
= us-gaap_DomesticCountryMember
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_LeaseholdImprovementsMember