IMPAIRMENT OF ASSETS: (Details Textual) - USD ($)	12 Months Ended
	Apr. 30, 2017	Apr. 30, 2016
Indefinite-lived Intangible Assets [Line Items]
Impairment of real estate assets	$ 150,000	$ 10,406,000
Original Value Of Impaired Real Estate	3,346,000	23,757,000
Fair Value Of Impaired Real Estate	3,232,000	21,264,000
Impairment of Long-Lived Assets Held-for-use		3,094,000
Impairment of Intangible Assets, Finite-lived		4,806,000
Land and Building [Member]
Indefinite-lived Intangible Assets [Line Items]
Impairment of Long-Lived Assets Held-for-use		2,970,000
Furniture and Fixtures [Member]
Indefinite-lived Intangible Assets [Line Items]
Impairment of Long-Lived Assets Held-for-use		124,000
Fulfillment Services [Member]
Indefinite-lived Intangible Assets [Line Items]
Impairment of real estate assets	0	7,900,000
Real Estate [Member]
Indefinite-lived Intangible Assets [Line Items]
Impairment of Real Estate	$ 150,000	$ 2,506,000