Property And Equipment (Details) - USD ($) $ in Thousands	Apr. 30, 2015	Apr. 30, 2014
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 6,427	$ 5,974
Less accumulated depreciation	(5,563)	(4,921)
Property and equipment, net	864	1,053
Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	5,630	5,279
Furniture And Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 797	$ 695