BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES, INVOL CONV OF ASSETS, FINANCING LIAB, VIE (Details) (USD $)	3 Months Ended			12 Months Ended
	Jul. 31, 2014		Jul. 31, 2013	Apr. 30, 2014 Unit Building	Apr. 30, 2013
Consolidated Balance Sheet [Abstract]
Redeemable noncontrolling interests consolidated real estate entities	$ 6,313,000		$ 5,949,000	$ 6,203,000	$ 5,937,000
Noncontrolling interests consolidated real estate entities	25,910,000			22,638,000
Total equity	726,197,000		765,357,000	720,546,000	755,444,000
Consolidated Statement of Equity [Abstract]
Net income attributable to Investors Real Estate Trust and nonredeemable noncontrolling interests	(308,000)		3,204,000
Contributions from nonredeemable noncontrolling interests - consolidated real estate entities	3,212,000	[1]
Balance	726,197,000		765,357,000	720,546,000	755,444,000
Impaired Long-Lived Assets Held and Used [Line Items]
Number of 32 unit buildings				2
Number of units in building				32
Number of buildings destroyed				1
Insurance proceeds received for redevelopment	2,000,000
PROCEEDS FROM FINANCING LIABILITY [Abstract]
Proceeds from sale of property			7,900,000
Contract for deed			29,000,000
Sale lease-back recorded in other liabilities			7,900,000
Financing liability balance	83,666,000		7,900,000	63,178,000
IRET - Minot Apartments, LLC [Member]
Variable Interest Entity [Line Items]
Estimated total costs of joint venture project				52,200,000
Percentage of ownership in VIE (in hundredths)	52.90%
IRET - Minot Apartments, LLC [Member] | Third Party Debt [Member]
Variable Interest Entity [Line Items]
Percentage of project financed (in hundredths)				69.00%
IRET - Minot Apartments, LLC [Member] | Debt from IRET [Member]
Variable Interest Entity [Line Items]
Percentage of project financed (in hundredths)				7.00%
IRET - Minot Apartments, LLC [Member] | Real Estate Development Company [Member]
Variable Interest Entity [Line Items]
Percentage of ownership in VIE (in hundredths)	47.10%
Chateau Apartment Fire, 2012 [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Insurance proceeds received for redevelopment			966,000
Gain from involuntary conversion			966,000
Chateau Apartment, Fire 2013 [Member] | Building One [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Number of units in building	15
Chateau Apartment, Fire 2013 [Member] | Building Two [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Number of units in building	57
Noncontrolling Interests [Member]
Consolidated Balance Sheet [Abstract]
Total equity	110,160,000		142,161,000	128,362,000	142,657,000
Consolidated Statement of Equity [Abstract]
Net income attributable to Investors Real Estate Trust and nonredeemable noncontrolling interests	(157,000)		126,000
Contributions from nonredeemable noncontrolling interests - consolidated real estate entities	3,212,000
Balance	110,160,000		142,161,000	128,362,000	142,657,000
Scenario, Previously Reported [Member]
Consolidated Balance Sheet [Abstract]
Total equity			771,306,000		761,381,000
Consolidated Statement of Equity [Abstract]
Net income attributable to Investors Real Estate Trust and nonredeemable noncontrolling interests			3,216,000
Balance			771,306,000		761,381,000
Scenario, Previously Reported [Member] | Noncontrolling Interests [Member]
Consolidated Balance Sheet [Abstract]
Total equity			148,110,000		148,594,000
Consolidated Statement of Equity [Abstract]
Net income attributable to Investors Real Estate Trust and nonredeemable noncontrolling interests			138,000
Balance			148,110,000		148,594,000
Restatement Adjustment [Member]
Consolidated Balance Sheet [Abstract]
Total equity			(5,949,000)		(5,937,000)
Consolidated Statement of Equity [Abstract]
Net income attributable to Investors Real Estate Trust and nonredeemable noncontrolling interests			(12,000)
Balance			(5,949,000)		(5,937,000)
Restatement Adjustment [Member] | Noncontrolling Interests [Member]
Consolidated Balance Sheet [Abstract]
Total equity			(5,949,000)		(5,937,000)
Consolidated Statement of Equity [Abstract]
Net income attributable to Investors Real Estate Trust and nonredeemable noncontrolling interests			(12,000)
Balance			$ (5,949,000)		$ (5,937,000)

[1] Consists of assumed debt (Homestead Garden I - $6.7 million, Homestead Garden II - $3.2 million, Silver Springs - $2.3 million) and value of land contributed by the joint