PROPERTY, PLANT AND EQUIPMENT (Details) - USD ($) $ in Thousands	Oct. 31, 2015	Apr. 30, 2015
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 39,206	$ 39,098
Less accumulated depreciation	(23,690)	(23,335)
Property, plant and equipment, net	15,516	15,763
Land, Buildings and Improvements [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	20,384	20,000
Furniture and equipment [Member]
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 18,822	$ 19,098