Seismic Equipment Lease Pool and Property and Equipment - Schedule of Seismic Equipment Lease Pool and Property and Equipment (Detail) - USD ($) $ in Thousands	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2017
Property, Plant and Equipment [Line Items]
Cost of property and equipment	$ 14,509	$ 14,324
Cost of seismic equipment lease pool and property and equipment	162,028	188,598
Less accumulated depreciation	(147,873)	(165,698)
Net book value of seismic equipment lease pool and property and equipment	14,155	22,900	$ 43,838
Recording channels
Property, Plant and Equipment [Line Items]
Cost of property and equipment	84,207	89,397
Other peripheral equipment
Property, Plant and Equipment [Line Items]
Cost of property and equipment	63,312	84,877
Cost of seismic equipment lease pool
Property, Plant and Equipment [Line Items]
Cost of property and equipment	147,519	174,274
Land and buildings
Property, Plant and Equipment [Line Items]
Cost of property and equipment	4,041	3,380
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Cost of property and equipment	9,897	10,222
Autos and trucks
Property, Plant and Equipment [Line Items]
Cost of property and equipment	$ 571	$ 722