DEFERRED REVENUE: (Details Textual)	12 Months Ended
	Apr. 30, 2017 USD ($) a	Apr. 30, 2016 USD ($) a	Oct. 31, 2015 USD ($) a
Deferred Revenue Arrangement [Line Items]
Area of Land | a	12,000	80	55,000
Deferred Revenue, Leases, Gross			$ 1,010,000
Operating Leases, Income Statement, Lease Revenue	$ 228,000	$ 228,000
Deferred Revenue, Leases, Net	$ 303,000
Description of Lessee Leasing Arrangements, Operating Leases	In addition, Lessee may extend the initial term of the Lease for an additional four years by paying ASW another payment of approximately $1,010,000