RETIREMENT PLANS (Details) - USD ($) $ in Thousands	12 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2016
Retirement Benefits [Abstract]
Maximum contribution each employee, towards 401(k) plan	5.00%
Employer contribution towards profit sharing plan and 401(k) plan	$ 838	$ 565	$ 836
Maximum contribution each employee, towards 401(k) plan, increase	1.00%
Discretionary employer contribution			3.50%