PROPERTY AND EQUIPMENT, NET (Summary of Property and Equipment) (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Mar. 31, 2023
Property and equipment
Gross property and equipment	$ 35,649	$ 35,234
Less: accumulated depreciation	(25,281)	(24,764)
Total property and equipment, net	10,368	10,470
Land and land improvements
Property and equipment
Gross property and equipment	433	433
Buildings and building improvements
Property and equipment
Gross property and equipment	9,504	9,491
Furniture, fixtures and office equipment
Property and equipment
Gross property and equipment	7,910	7,782
Leasehold Improvements
Property and equipment
Gross property and equipment	540	540
Equipment leased to customers
Property and equipment
Gross property and equipment	4,997	4,997
Plant equipment
Property and equipment
Gross property and equipment	11,135	11,234
Vehicles
Property and equipment
Gross property and equipment	1,027	720
Construction in Progress
Property and equipment
Gross property and equipment	$ 103	$ 37