COMMITMENTS AND CONTINGENCIES, Development, Expansion and Renovation Projects (Details) $ in Thousands	12 Months Ended
Apr. 30, 2016 USD ($) ft² item
Real Estate Properties [Line Items]
Anticipated Total Cost	$ 182,255
Project costs incurred to date	167,532
Other [Member]
Real Estate Properties [Line Items]
Project costs incurred to date	$ 3,729
Multi-Family Residential [Member] \| 163 unit - Deer Ridge - Jamestown, ND
Real Estate Properties [Line Items]
Number of apartment units \| item	163
Anticipated Total Cost	$ 24,837
Project costs incurred to date	$ 24,837
Multi-Family Residential [Member] \| 251 unit - Cardinal Point - Grand Forks, ND
Real Estate Properties [Line Items]
Number of apartment units \| item	251
Anticipated Total Cost	$ 52,344
Project costs incurred to date	$ 49,732
Multi-Family Residential [Member] \| 71 France Phase I, II, III - Edina, MN [Member]
Real Estate Properties [Line Items]
Number of apartment units \| item	241
Anticipated Total Cost	$ 73,290
Project costs incurred to date	$ 71,727
Estimated quarter for completion	1Q
Estimated year for completion	2017
Costs related to development projects placed in service in phases	$ 41,300
Interest in joint venture (in hundredths)	52.60%
Area of real estate property \| ft²	20,956
Multi-Family Residential [Member] \| Monticello Crossings - Monticello, MN
Real Estate Properties [Line Items]
Number of apartment units \| item	202
Anticipated Total Cost	$ 31,784
Project costs incurred to date	$ 17,507
Estimated quarter for completion	2Q
Estimated year for completion	2017

Estimated cost of project.

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Refers to the costs related to development projects placed in service in phases.

+ References

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Number of apartment units.

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The quarter in which a construction project is estimated to be completed.

+ References

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The year in which a construction project is estimated to be completed.

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Area of a real estate property.

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- Definition

The capitalized costs incurred (excluded from amortization), as of the date of the balance sheet, to obtain access to proved reserves and to provide facilities for extracting, treating, gathering and storing the oil and gas.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-10.(c)(7)(ii))
-URI http://asc.fasb.org/extlink&oid=50486907&loc=d3e511914-122862

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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