FAIR VALUE MEASUREMENTS (Details) $ in Thousands	Jan. 31, 2017 USD ($)	Apr. 30, 2016 USD ($) property
FINANCIAL LIABILITIES [Abstract]
Mortgages payable	$ 688,424	$ 812,393
Carrying Amount [Member]
FINANCIAL ASSETS [Abstract]
Cash and cash equivalents	56,999	66,698
FINANCIAL LIABILITIES [Abstract]
Other debt	39,438	82,026
Lines of credit	157,000	17,500
Mortgages payable	693,949	817,324
Mortgages payable related to assets held for sale	53,489	68,824
Fair Value [Member]
FINANCIAL ASSETS [Abstract]
Cash and cash equivalents	56,999	66,698
FINANCIAL LIABILITIES [Abstract]
Other debt	39,438	82,026
Lines of credit	157,000	17,500
Mortgages payable	695,495	866,649
Mortgages payable related to assets held for sale	$ 53,321	78,690
Nonrecurring [Member]
Fair Value Measurements on a Nonrecurring Basis [Abstract]
Real estate held for sale		$ 6,650
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 held for sale		$ 6,650

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

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

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash
-URI http://asc.fasb.org/extlink&oid=6506951

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Cash Equivalents
-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Line-of-Credit Arrangement
-URI http://asc.fasb.org/extlink&oid=6517033

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Fair value portion of contractual obligation to pay money on demand or on fixed or determinable dates.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20, 22
-Article 5

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