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Seismic Equipment Lease Pool and Property and Equipment - Schedule of Seismic Equipment Lease Pool and Property and Equipment (Detail) (USD $)
In Thousands, unless otherwise specified
Jan. 31, 2014
Jan. 31, 2013
Jan. 31, 2012
Property, Plant and Equipment [Line Items]      
Cost of property and equipment $ 10,040 $ 10,013  
Cost of seismic equipment lease pool and property and equipment 271,684 251,408  
Less accumulated depreciation (142,111) (131,800)  
Seismic equipment lease pool and property and equipment, net 129,573 119,608 120,377
Channel Boxes [Member]
      
Property, Plant and Equipment [Line Items]      
Cost of property and equipment 148,004 126,600  
Peripheral Equipment [Member]
      
Property, Plant and Equipment [Line Items]      
Cost of property and equipment 113,640 114,795  
Seismic Equipment Lease Pool [Member]
      
Property, Plant and Equipment [Line Items]      
Cost of property and equipment 261,644 241,395  
Land and Buildings [Member]
      
Property, Plant and Equipment [Line Items]      
Cost of property and equipment 366 366  
Furniture and Fixtures [Member]
      
Property, Plant and Equipment [Line Items]      
Cost of property and equipment 8,904 8,899  
Autos and Trucks [Member]
      
Property, Plant and Equipment [Line Items]      
Cost of property and equipment $ 770 $ 748