MORTGAGES PAYABLE AND LINE OF CREDIT, Line of Credit (Details) - Line of Credit [Member] $ in Millions	9 Months Ended
Jan. 31, 2016 USD ($) Property	Apr. 30, 2015 USD ($)
Line of Credit [Abstract]
Lending commitments	$ 100.0
Number of properties securing line of credit \| Property	17
Line of credit, current interest rate	4.75%
Line of credit, minimum outstanding principal balance	$ 17.5
Borrowed amount	$ 17.5	$ 60.5
Debt service coverage on aggregate assets	1.25
Debt service coverage on individual assets	1.00
Minimum depository accounts	$ 6.0
Non-interest bearing account	$ 1.5

Financial covenant requiring the entity to maintain a specific debt service coverage on aggregate assets.

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Financial covenant requiring the entity to maintain a specific debt service coverage on individual assets.

+ References

No definition available.

+ Details

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Namespace Prefix:	iret_
Data Type:	xbrli:pureItemType
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Period Type:	duration

- Definition

Line of credit, minimum outstanding principal balance.

+ References

No definition available.

+ Details

Name:	iret_LineOfCreditMinimumOutstandingPrincipalBalance
Namespace Prefix:	iret_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The minimum amount of deposit to be maintained.

+ References

No definition available.

+ Details

Name:	iret_MinimumDeposit
Namespace Prefix:	iret_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The number of properties used as security under the line of credit.

+ References

No definition available.

+ Details

Name:	iret_NumberOfPropertiesSecuringLineOfCredit
Namespace Prefix:	iret_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ 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 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 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of domestic noninterest-bearing deposits held by the entity, which may include demand deposits, checking, brokered and retail deposits.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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