OPERATING SEGMENT (Details) $ in Thousands	3 Months Ended								6 Months Ended	12 Months Ended
	Apr. 30, 2018 USD ($)	Jan. 31, 2018 USD ($)	Oct. 31, 2017 USD ($)	Jul. 31, 2017 USD ($)	Apr. 30, 2017 USD ($)	Jan. 31, 2017 USD ($)	Oct. 31, 2016 USD ($)	Jul. 31, 2016 USD ($)	Oct. 31, 2017 segment	Apr. 30, 2018 USD ($)	Apr. 30, 2017 USD ($)	Apr. 30, 2016 USD ($) segment	Apr. 30, 2015 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment									2			5
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUE	$ 44,185	$ 42,716	$ 41,866	$ 40,978	$ 42,811	$ 39,797	$ 39,195	$ 38,301		$ 169,745	$ 160,104	$ 145,500
Net operating income										96,711	95,778	87,352
Casualty loss										(500)	(414)	(238)
Depreciation and amortization										(82,070)	(44,253)	(39,273)
Impairment of real estate investments										(18,065)	(57,028)	(5,543)
General and administrative expenses										(14,203)	(15,871)	(13,498)
Acquisition and investment related costs										(51)	(3,276)	(830)
Interest expense										(34,178)	(34,314)	(28,417)
Loss on extinguishment of debt										(940)	(1,651)	(106)
Interest and other income										1,508	1,146	385
Loss before gain on sale of real estate and other investments, gain on bargain purchase and income from discontinued operations										(57,314)	(64,929)	(3,882)
Gain on sale of real estate and other investments										20,120	18,701	9,640
Gain on bargain purchase										0	0	3,424
Income (loss) from continuing operations										(37,194)	(46,228)	9,182
Income from discontinued operations										164,823	76,753	67,420
NET INCOME										127,629	30,525	76,602
Segment Assets [Abstract]
Property owned	1,669,764				1,358,529					1,669,764	1,358,529
Less accumulated depreciation	(311,324)				(255,599)					(311,324)	(255,599)
Total property owned	1,358,440				1,102,930					1,358,440	1,102,930
Assets held for sale and assets of discontinued operations	0				283,023					0	283,023
Cash and cash equivalents	11,891				28,819					11,891	28,819	66,698	$ 48,970
Restricted cash	4,225				27,981					4,225	27,981
Other assets	30,297				13,306					30,297	13,306
Unimproved land	11,476				18,455					11,476	18,455
Mortgage loans receivable	10,329				0					10,329	0
TOTAL ASSETS	1,426,658				1,474,514					1,426,658	1,474,514
Multi-Family Residential [Member] | Operating Segments [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUE										159,983	142,214	129,049
Net operating income										89,523	81,319	74,287
Segment Assets [Abstract]
Property owned	1,606,421				1,260,541					1,606,421	1,260,541
Less accumulated depreciation	(294,477)				(232,592)					(294,477)	(232,592)
Total property owned	1,311,944				1,027,949					1,311,944	1,027,949
All Other [Member] | Operating Segments [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
REVENUE										9,762	17,890	16,451
Net operating income										7,188	14,459	13,065
Segment Assets [Abstract]
Property owned	63,343				97,988					63,343	97,988
Less accumulated depreciation	(16,847)				(23,007)					(16,847)	(23,007)
Total property owned	$ 46,496				$ 74,981					46,496	74,981
Real Estate [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Cost of revenue										(73,034)	(64,326)	(58,148)
Cost of revenue										(73,034)	(64,326)	(58,148)
Real Estate [Member] | Multi-Family Residential [Member] | Operating Segments [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Cost of revenue										(70,460)	(60,895)	(54,762)
Cost of revenue										(70,460)	(60,895)	(54,762)
Real Estate [Member] | All Other [Member] | Operating Segments [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Cost of revenue										(2,574)	(3,431)	(3,386)
Cost of revenue										(2,574)	(3,431)	(3,386)
Management Service [Member]
Segment Reporting Information, Profit (Loss) [Abstract]
Cost of revenue										(5,526)	(5,046)	(3,714)
Cost of revenue										$ (5,526)	$ (5,046)	$ (3,714)