BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES, Identified Intangible Assets and Liabilities and Goodwill (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Jan. 31, 2016 USD ($)	Jan. 31, 2015 USD ($)	Jan. 31, 2016 USD ($) Property	Jan. 31, 2015 USD ($) Property	Apr. 30, 2015 USD ($)
Identified Intangible Assets and Liabilities and Goodwill [Abstract]
New intangible assets			$ 1,300,000	$ 365,000
Addition to intangible liabilities			$ 101,000	$ 0
Weighted average lives of intangible assets and intangible liabilities			9 months 18 days	6 months
Identified intangible assets (included in intangible assets) [Abstract]
Gross carrying amount	$ 45,127,000		$ 45,127,000		$ 45,823,000
Accumulated amortization	(21,214,000)		(21,214,000)		(19,610,000)
Net carrying amount	23,913,000		23,913,000		26,213,000
Identified intangible liabilities (included in other liabilities) [Abstract]
Gross carrying amount	159,000		159,000		82,000
Accumulated amortization	(49,000)		(49,000)		(61,000)
Net carrying amount	110,000		110,000		21,000
Amortization of above and below market leases	3,000	$ 7,000	14,000	$ 18,000
Amortization of all other identified intangible assets	1,400,000	$ 1,100,000	3,600,000	4,000,000
Estimated annual amortization of acquired below-market leases, net of acquired above-market leases [Abstract]
2017					3,000
2018					(11,000)
2019					(20,000)
2020					(16,000)
2021					(13,000)
Estimated annual amortization of all other identified intangible assets [Abstract]
2017					3,835,000
2018					3,605,000
2019					3,507,000
2020					3,440,000
2021					3,312,000
Goodwill [Line Items]
Goodwill	$ 1,715,000		1,715,000		1,718,000
Goodwill impairment			0		0
Goodwill derecognized			196,000	11,000	$ 0
Goodwill recognized			$ 0	$ 852,000
Commercial [Member]
Goodwill [Line Items]
Number of real estate properties sold | Property			8
Multifamily [Member]
Goodwill [Line Items]
Number of real estate properties sold | Property				1