INCOME TAXES: (Details Textual) - USD ($)	12 Months Ended
	Apr. 30, 2016	Apr. 30, 2015
Operating Loss Carryforwards State Subject To Expiration Current	$ 112,055,000
Operating Loss Carryforwards State Subject To Expiration In One Years	0
Operating Loss Carryforwards State Subject To Expiration In Two Years	0
Operating Loss Carryforwards State Subject To Expiration In Three Years	0
Operating Loss Carryforwards State Subject To Expiration In Four Years	1,969,000
Operating Loss Carryforwards State Subject To Expiration In five Years	32,000
Operating Loss Carryforwards State Subject To Expiration In Thereafter	110,054,000
Business Acquisition Purchase Price Allocation Goodwill	7,419,000
Unrecognized Tax Benefits, Period Increase (Decrease)	58,000	$ 58,000
Deferred Tax Assets, Valuation Allowance	4,567,000	3,657,000
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	910,000	1,030,000
State and Local Jurisdiction [Member]
Operating Loss Carryforwards	$ 194,000	$ 14,416,000