DISCONTINUED OPERATIONS (Details) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Oct. 31, 2013	Oct. 31, 2012	Oct. 31, 2013 Property	Oct. 31, 2012	Apr. 30, 2013 Property
DISCONTINUED OPERATIONS [Abstract]
Number Of Condominium Units Sold					4
Number of industrial held for sale			1
REVENUE
Real estate rentals	$ 54,836,000	$ 51,403,000	$ 108,812,000	$ 100,775,000
Tenant reimbursement	11,354,000	10,855,000	22,885,000	20,828,000
TOTAL REVENUE	66,190,000	62,258,000	131,697,000	121,603,000
EXPENSES
Depreciation/amortization related to real estate investments	16,453,000	15,009,000	34,600,000	29,700,000
Utilities	5,239,000	4,798,000	10,192,000	8,961,000
Maintenance	7,203,000	6,375,000	14,981,000	13,539,000
Real estate taxes	8,432,000	7,836,000	16,877,000	15,721,000
Insurance	1,421,000	916,000	2,729,000	1,786,000
Property management expenses	4,217,000	3,892,000	8,380,000	7,541,000
Other expenses	678,000	513,000	1,357,000	1,032,000
Amortization related to non-real estate investments	804,000	749,000	1,752,000	1,501,000
Impairment of real estate investments			1,860,000	0
TOTAL EXPENSES	46,977,000	42,381,000	96,593,000	84,504,000
Interest expense	(14,848,000)	(15,727,000)	(29,500,000)	(31,544,000)
Gain (loss) on sale of discontinued operations			6,641,000	2,680,000
INCOME FROM DISCONTINUED OPERATIONS	5,280,000	3,394,000	6,081,000	3,843,000
Discontinued Operations [Member]
REVENUE
Real estate rentals	855,000	2,303,000	2,134,000	4,695,000
Tenant reimbursement	460,000	699,000	1,123,000	1,382,000
TOTAL REVENUE	1,315,000	3,002,000	3,257,000	6,077,000
EXPENSES
Depreciation/amortization related to real estate investments	222,000	748,000	668,000	1,510,000
Utilities	(21,000)	91,000	77,000	159,000
Maintenance	38,000	180,000	174,000	441,000
Real estate taxes	272,000	477,000	730,000	982,000
Insurance	30,000	47,000	72,000	99,000
Property management expenses	44,000	116,000	134,000	234,000
Other expenses	0	10,000	0	16,000
Amortization related to non-real estate investments	35,000	50,000	80,000	131,000
Impairment of real estate investments	57,000	0	1,595,000	0
TOTAL EXPENSES	677,000	1,719,000	3,530,000	3,572,000
Operating (loss) income	638,000	1,283,000	(273,000)	2,505,000
Interest expense	(56,000)	(642,000)	(287,000)	(1,342,000)
(Loss) income from discontinued operations before gain (loss) on sale	582,000	641,000	(560,000)	1,163,000
Gain (loss) on sale of discontinued operations	4,698,000	2,753,000	6,641,000	2,680,000
INCOME FROM DISCONTINUED OPERATIONS	$ 5,280,000	$ 3,394,000	$ 6,081,000	$ 3,843,000