DISCONTINUED OPERATIONS (Details)	3 Months Ended								12 Months Ended
	Apr. 30, 2016 USD ($)	Jan. 31, 2016 USD ($)	Oct. 31, 2015 USD ($)	Jul. 31, 2015 USD ($)	Apr. 30, 2015 USD ($)	Jan. 31, 2015 USD ($)	Oct. 31, 2014 USD ($)	Jul. 31, 2014 USD ($)	Apr. 30, 2016 USD ($) loan property	Apr. 30, 2015 USD ($) property	Apr. 30, 2014 USD ($) property
REVENUE
Real estate rentals									$ 170,698,000	$ 159,969,000	$ 145,028,000
Tenant reimbursement									17,622,000	19,352,000	19,562,000
TOTAL REVENUE	$ 48,523,000	$ 48,406,000	$ 46,346,000	$ 45,045,000	$ 45,141,000	$ 45,630,000	$ 45,236,000	$ 43,314,000	188,320,000	179,321,000	164,590,000
EXPENSES
Property operating expenses, excluding real estate taxes									58,859,000	53,535,000	50,552,000
Real estate taxes									20,241,000	19,602,000	18,704,000
Depreciation and amortization									49,832,000	42,784,000	39,712,000
Impairment of real estate investments									5,543,000	4,663,000	7,700,000
Other expenses									2,231,000	1,647,000	1,850,000
Other property expenses									830,000
TOTAL EXPENSES									148,803,000	134,417,000	129,540,000
Operating income (loss)									39,517,000	44,904,000	37,530,000
Interest expense									(35,768,000)	(34,447,000)	(33,729,000)
Gain on extinguishment of debt									(106,000)
Interest income									2,256,000	2,238,000	1,906,000
Other income									317,000	718,000	242,000
Gain on sale of discontinued operations									33,423,000	6,093,000	6,948,000
INCOME (LOSS) FROM DISCONTINUED OPERATIONS									57,322,000	9,178,000	(22,838,000)
Property Sale Data
Gain on sale of discontinued operations									33,423,000	$ 6,093,000	6,948,000
Discontinued Operations [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of real estate properties classified as discontinued operations | property										0
REVENUE
Real estate rentals									43,544,000	$ 75,883,000	78,066,000
Tenant reimbursement									8,684,000	24,466,000	27,301,000
TRS senior housing revenue									3,955,000	3,520,000	1,627,000
TOTAL REVENUE									56,183,000	103,869,000	106,994,000
EXPENSES
Property operating expenses, excluding real estate taxes									10,252,000	23,517,000	25,735,000
Real estate taxes									5,777,000	14,343,000	15,229,000
Depreciation and amortization									14,166,000	27,823,000	32,216,000
Impairment of real estate investments									440,000	1,442,000	36,726,000
TRS senior housing expenses									3,366,000	2,997,000	1,331,000
Other expenses										1,000	3,000
TOTAL EXPENSES									34,001,000	70,123,000	111,240,000
Operating income (loss)									22,182,000	33,746,000	(4,246,000)
Interest expense									(18,406,000)	(24,573,000)	(25,834,000)
Gain on extinguishment of debt									29,336,000
Interest income									1,000		2,000
Other income									427,000	5,000	241,000
Income (Loss) from discontinued operations before gain on sale									33,540,000	9,178,000	(29,837,000)
Gain on sale of discontinued operations									23,782,000		6,999,000
INCOME (LOSS) FROM DISCONTINUED OPERATIONS									57,322,000	9,178,000	(22,838,000)
Default interest									4,700,000	528,000
Non-recourse loan	$ 122,600,000				$ 122,600,000				122,600,000	122,600,000
Gain on extinguishment of debt from transfer of ownership									$ 36,500,000
Number of loan properties | loan									9
Property Sale Data
Sales price									$ 373,460,000		80,883,000
Net book value and sales costs									(349,678,000)		(73,884,000)
Gain on sale of discontinued operations									23,782,000		6,999,000
Discontinued Operations [Member] | Multi-Family Residential [Member]
EXPENSES
INCOME (LOSS) FROM DISCONTINUED OPERATIONS											(99,000)
Discontinued Operations [Member] | Commercial Healthcare [Member]
EXPENSES
INCOME (LOSS) FROM DISCONTINUED OPERATIONS									5,926,000	6,832,000	4,223,000
Discontinued Operations [Member] | Other Segments [Member]
EXPENSES
INCOME (LOSS) FROM DISCONTINUED OPERATIONS									$ 51,396,000	$ 2,346,000	$ (26,962,000)
Discontinued Operations, Disposed of by Sale [Member] | Multi-Family Residential [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of real estate properties disposed | property											2
Discontinued Operations, Disposed of by Sale [Member] | Office [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of real estate properties classified as discontinued operations | property									48
Number of real estate properties disposed | property											3
Discontinued Operations, Disposed of by Sale [Member] | Commercial Healthcare [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of real estate properties classified as discontinued operations | property									1
Discontinued Operations, Disposed of by Sale [Member] | Industrial [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of real estate properties disposed | property											12
Discontinued Operations, Disposed of by Sale [Member] | Retail [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of real estate properties classified as discontinued operations | property									17
Number of real estate properties disposed | property											3
Discontinued Operations, Held-for-sale [Member] | Senior Housing properties [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Number of properties classified as held for sale | property									34