DISCONTINUED OPERATIONS (Details) (USD $)	3 Months Ended
	Jul. 31, 2013	Jul. 31, 2012
DISCONTINUED OPERATIONS [Abstract]
Number Of Condominium Units Sold		2
Number of retail properties sold	1
Number of industrial sold	4
Number of industrial held for sale	2
REVENUE
Real estate rentals	$ 55,039,000	$ 50,458,000
Tenant reimbursement	12,143,000	10,517,000
TOTAL REVENUE	67,182,000	60,975,000
EXPENSES
Depreciation/amortization related to real estate investments	18,528,000	15,063,000
Utilities	5,051,000	4,194,000
Maintenance	7,912,000	7,312,000
Real estate taxes	8,862,000	8,242,000
Insurance	1,347,000	901,000
Property management expenses	4,242,000	3,701,000
Other expenses	679,000	519,000
Amortization related to non-real estate investments	990,000	822,000
Impairment of real estate investments	1,803,000	0
TOTAL EXPENSES	51,999,000	43,185,000
Interest expense	(14,799,000)	(16,069,000)
Gain (loss) on sale of discontinued operations	1,943,000	(73,000)
INCOME FROM DISCONTINUED OPERATIONS	1,656,000	133,000
Discontinued Operations [Member]
REVENUE
Real estate rentals	216,000	1,306,000
Tenant reimbursement	51,000	139,000
TOTAL REVENUE	267,000	1,445,000
EXPENSES
Depreciation/amortization related to real estate investments	65,000	390,000
Utilities	0	37,000
Maintenance	2,000	113,000
Real estate taxes	41,000	148,000
Insurance	3,000	21,000
Property management expenses	11,000	65,000
Other expenses	0	6,000
Amortization related to non-real estate investments	3,000	11,000
Impairment of real estate investments	345,000	0
TOTAL EXPENSES	470,000	791,000
Operating (loss) income	(203,000)	654,000
Interest expense	(84,000)	(448,000)
(Loss) income from discontinued operations before gain (loss) on sale	(287,000)	206,000
Gain (loss) on sale of discontinued operations	1,943,000	(73,000)
INCOME FROM DISCONTINUED OPERATIONS	$ 1,656,000	$ 133,000