PROPERTY, PLANT AND EQUIPMENT - Summary of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Jan. 31, 2020	Jan. 31, 2019
Property, plant and equipment
Property and equipment, gross	$ 37,525	$ 31,709
Less - accumulated depreciation	14,986	11,931
Property, plant and equipment, net	22,539	19,778
Land and improvements
Property, plant and equipment
Property and equipment, gross	863	863
Building and improvements
Property, plant and equipment
Property and equipment, gross	5,696	6,000
Furniture, machinery and equipment
Property, plant and equipment
Property and equipment, gross	18,900	17,779
Trucks and other vehicles
Property, plant and equipment
Property and equipment, gross	5,213	4,918
Project development costs (Note 3)
Property, plant and equipment
Property and equipment, gross	$ 6,853	$ 2,149

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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