FAIR VALUE MEASUREMENTS (Details) $ in Thousands	3 Months Ended
Jul. 31, 2016 USD ($) property	Apr. 30, 2016 USD ($) property
FINANCIAL LIABILITIES [Abstract]
Mortgages payable	$ 812,082	$ 812,393
Carrying Amount [Member]
FINANCIAL ASSETS [Abstract]
Cash and cash equivalents	54,438	66,698
FINANCIAL LIABILITIES [Abstract]
Other debt	78,383	82,026
Lines of credit	17,500	17,500
Mortgages payable	816,626	817,324
Mortgages payable related to assets held for sale	67,794	68,824
Fair Value [Member]
FINANCIAL ASSETS [Abstract]
Cash and cash equivalents	54,438	66,698
FINANCIAL LIABILITIES [Abstract]
Other debt	78,383	82,026
Lines of credit	17,500	17,500
Mortgages payable	884,809	866,649
Mortgages payable related to assets held for sale	79,632	78,690
Nonrecurring [Member]
Fair Value Measurements on a Nonrecurring Basis [Abstract]
Real estate investments	$ 35,281
Real estate held for sale		$ 6,650
Number of real estate properties with fair value measured by independent appraisal \| property	1
Number of real estate properties with fair value measured by discounted cash flow \| property	3
Anticipated holding period	10 years
Discount rate (as a percent)	9.00%
Terminal capitalizaton (as a percent)	9.00%
Nonrecurring [Member] \| Discontinued Operations, Held-for-sale [Member]
Fair Value Measurements on a Nonrecurring Basis [Abstract]
Number of real estate properties with fair value measured by individual market offer \| property		2
Nonrecurring [Member] \| Level 3 [Member]
Fair Value Measurements on a Nonrecurring Basis [Abstract]
Real estate investments	$ 35,281
Real estate held for sale		$ 6,650

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Number of properties using discounted cash flow to measure fair value.

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Number of properties using an independent appraisal to measure fair value.

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Number of properties using individual market offers to measure fair value.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents loan receivable as presented on the statement of financial position which may include investments in land and buildings, excluding real estate considered to be inventory of the entity.

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Fair value portion of mortgages payable related to assets held for sale.

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This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents loan receivable as presented on the statement of financial position which may include investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Ratio of the net operating income produced by an asset and its capital cost (original prices paid to buy the asset), used as an input to measure fair value.

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Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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Fair value portion of contractual arrangement with a lender under which borrowings can be made up to a specific amount at any point in time.

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
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-Section 02
-Paragraph 20, 22
-Article 5

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