PROPERTY AND EQUIPMENT (Summary of Property and Equipment) (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Mar. 31, 2022
Property and equipment
Gross property and equipment	$ 35,234	$ 34,990
Less: accumulated depreciation and amortization	(24,764)	(23,524)
Net property and equipment	10,470	11,466
Land and land improvements
Property and equipment
Gross property and equipment	433	433
Buildings and building improvements
Property and equipment
Gross property and equipment	9,491	9,491
Furniture, fixtures and office equipment
Property and equipment
Gross property and equipment	7,782	7,650
Leasehold Improvements
Property and equipment
Gross property and equipment	540	490
Equipment leased to customers
Property and equipment
Gross property and equipment	4,997	4,997
Plant equipment
Property and equipment
Gross property and equipment	11,234	11,130
Vehicles
Property and equipment
Gross property and equipment	720	796
Construction in progress
Property and equipment
Gross property and equipment	$ 37	$ 3

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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