BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $)	12 Months Ended
	Apr. 30, 2014 Redemption Property		Apr. 30, 2013 Property		Apr. 30, 2012 Unit Property		Oct. 31, 2012 Property	Apr. 30, 2011
BASIS OF PRESENTATION [Abstract]
Interest in operating partnership (in hundredths)	83.80%		82.40%
Percentage of general interest partnership (in hundredths)	100.00%
Redemption basis	1:1
Redemptions by limited partner, maximum	2
Number of units to redeem, minimum (in units)	1,000
Period to hold the beneficial interest, minimum	1 year
REAL ESTATE INVESTMENTS [Abstract]
Number of year after date of acquisition related to adjustment of real estate preliminary allocations of purchase price	1 year
Impairment of retail property	$ 44,426,000		$ 305,000		$ 428,000
Number of impaired properties	15		1		2
Goodwill impairment	0		0		7,000
Number of real estate properties classified as held for sale	1		0
IDENTIFIED INTANGIBLE ASSETS AND LIABILITIES AND GOODWILL [Abstract]
New intangible assets	900,000		1,600,000
Addition to intangible liabilities	0		0
Weighted average lives of intangible assets and intangible liabilities	0 years 8 months 12 days		0 years 6 months
Goodwill book value	1,100,000		1,106,000	[1]
Recognized impairment goodwill	0		0		7,000
Finite-Lived Intangible Assets [Line Items]
Goodwill derecognized	7,000		14,000		0
PROPERTY AND EQUIPMENT [Abstract]
Property and equipment cost	3,700,000		2,900,000
Accumulated depreciation	2,041,000		1,673,000
Compensating Balances [Line Items]
Compensating balance	7,900,000
Certificates of deposit	329,000
Decrease in lender holdbacks	3,780,000		1,891,000		5,681,000
Increase in lender holdbacks for improvements	11,045,000		2,466,000		1,730,000
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance at beginning of year	563,000
Balance at close of year	248,000		563,000
INCOME TAXES [Abstract]
Minimum dividend distribution percentage (in hundredths)	90.00%
Dividend distribution percentage (in hundredths)	90.00%		90.00%		90.00%
Distribution of federal income tax (in hundredths)			28.41%		23.17%
Distribution of capital gain (in hundredths)			3.09%		2.41%
Distribution made as return of capital (in hundredths)			68.50%		74.42%
Unusual or Infrequent Item [Line Items]
Number of 32-unit buildings					2
Number of units in building					32
Number of buildings destroyed					2		1
Total gain on involuntary conversion	2,480,000		5,084,000		274,000
Insurance proceeds received for reimbursement for business interruption (loss of rents)	409,000		666,000
Involuntary Conversion Of Assets Line Item	7,100,000
Consolidated Balance Sheet [Abstract]
Redeemable noncontrolling interests consolidated real estate entities	6,203,000		5,937,000	[1]
Noncontrolling interests consolidated real estate entities	22,638,000		20,118,000	[1]
Balance April 30, 2013	720,546,000	[1]	755,444,000	[1]	565,263,000	[1]		544,290,000	[1]
Consolidated Statement of Equity [Abstract]
Net income attributable to Investors Real Estate Trust and nonredeemable noncontrolling interests	(17,207,000)	[1]	29,967,000	[1]	9,694,000	[1]
Contributions from nonredeemable noncontrolling interests consolidated real estate entities	3,895,000	[1]	6,483,000	[1]
Balance April 30, 2013	720,546,000	[1]	755,444,000	[1]	565,263,000	[1]		544,290,000	[1]
NONCONTROLLING INTERESTS [Member]
Consolidated Balance Sheet [Abstract]
Balance April 30, 2013	128,362,000	[1]	142,657,000	[1]	132,274,000	[1]		132,600,000	[1]
Consolidated Statement of Equity [Abstract]
Net income attributable to Investors Real Estate Trust and nonredeemable noncontrolling interests	(4,033,000)	[1]	4,437,000	[1]	1,482,000	[1]
Contributions from nonredeemable noncontrolling interests consolidated real estate entities	3,895,000	[1]	6,483,000	[1]
Balance April 30, 2013	128,362,000	[1]	142,657,000	[1]	132,274,000	[1]		132,600,000	[1]
Scenario, Previously Reported [Member]
Consolidated Balance Sheet [Abstract]
Redeemable noncontrolling interests consolidated real estate entities			0
Noncontrolling interests consolidated real estate entities			26,055,000
Balance April 30, 2013			761,381,000
Consolidated Statement of Equity [Abstract]
Net income attributable to Investors Real Estate Trust and nonredeemable noncontrolling interests			29,972,000
Contributions from nonredeemable noncontrolling interests consolidated real estate entities			12,415,000
Balance April 30, 2013			761,381,000
Scenario, Previously Reported [Member] | NONCONTROLLING INTERESTS [Member]
Consolidated Balance Sheet [Abstract]
Balance April 30, 2013			148,594,000
Consolidated Statement of Equity [Abstract]
Net income attributable to Investors Real Estate Trust and nonredeemable noncontrolling interests			4,442,000
Contributions from nonredeemable noncontrolling interests consolidated real estate entities			12,415,000
Balance April 30, 2013			148,594,000
Restatement Adjustment [Member]
Consolidated Balance Sheet [Abstract]
Redeemable noncontrolling interests consolidated real estate entities			5,937,000
Noncontrolling interests consolidated real estate entities			(5,937,000)
Balance April 30, 2013			(5,937,000)
Consolidated Statement of Equity [Abstract]
Net income attributable to Investors Real Estate Trust and nonredeemable noncontrolling interests			(5,000)
Contributions from nonredeemable noncontrolling interests consolidated real estate entities			(5,932,000)
Balance April 30, 2013			(5,937,000)
Restatement Adjustment [Member] | NONCONTROLLING INTERESTS [Member]
Consolidated Balance Sheet [Abstract]
Balance April 30, 2013			(5,937,000)
Consolidated Statement of Equity [Abstract]
Net income attributable to Investors Real Estate Trust and nonredeemable noncontrolling interests			(5,000)
Contributions from nonredeemable noncontrolling interests consolidated real estate entities			(5,932,000)
Balance April 30, 2013			(5,937,000)
Flood [Member]
Unusual or Infrequent Item [Line Items]
Total gain on involuntary conversion	0		2,821,000		274,000
Proceeds from final settlement	8,500,000
2012 Fire [Member]
Unusual or Infrequent Item [Line Items]
Total gain on involuntary conversion	2,480,000		2,263,000		0
Proceeds from final settlement	5,100,000
2013 Fire [Member]
Unusual or Infrequent Item [Line Items]
Insurance proceeds received for flood clean up costs and redevelopment	1,000,000
Number of 15-unit buildings	1
Number of 57-unit buildings	1
Lost net operating income	882,000
Allowance for Doubtful Accounts [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance at beginning of year	1,393,000		1,363,000		1,316,000
Provision	434,000		665,000		298,000
Write-off	(783,000)		(635,000)		(251,000)
Balance at close of year	1,044,000		1,393,000		1,363,000
Dacotah Bank, Minot, North Dakota [Member]
Compensating Balances [Line Items]
Compensating balance	350,000
Remaining terms of certificates of deposit	2 years
United Community Bank, Minot, North Dakota [Member]
Compensating Balances [Line Items]
Compensating balance	275,000
Remaining terms of certificates of deposit	6 months
First International Bank, Watford City, North Dakota [Member]
Compensating Balances [Line Items]
Compensating balance	6,100,000
Peoples State Bank of Velva, North Dakota [Member]
Compensating Balances [Line Items]
Compensating balance	225,000
Associated Bank, Green Bay, Wisconsin [Member]
Compensating Balances [Line Items]
Compensating balance	600,000
American National Bank, Omaha, Nebraska [Member]
Compensating Balances [Line Items]
Compensating balance	400,000
Buildings and Improvements [Member] | Minimum [Member]
REAL ESTATE INVESTMENTS [Abstract]
Estimated useful life of assets (in years)	20 years
Buildings and Improvements [Member] | Maximum [Member]
REAL ESTATE INVESTMENTS [Abstract]
Estimated useful life of assets (in years)	40 years
Furniture, Fixtures and Equipment [Member] | Minimum [Member]
REAL ESTATE INVESTMENTS [Abstract]
Estimated useful life of assets (in years)	5 years
Furniture, Fixtures and Equipment [Member] | Maximum [Member]
REAL ESTATE INVESTMENTS [Abstract]
Estimated useful life of assets (in years)	12 years
Renovations and Improvements [Member] | Minimum [Member]
REAL ESTATE INVESTMENTS [Abstract]
Estimated useful life of assets (in years)	5 years
Renovations and Improvements [Member] | Maximum [Member]
REAL ESTATE INVESTMENTS [Abstract]
Estimated useful life of assets (in years)	10 years
Grand Chute, Wisconsin [Member]
REAL ESTATE INVESTMENTS [Abstract]
Impairment of retail property					293,000
Number of impaired properties					8
Discontinued Operations [Member]
REAL ESTATE INVESTMENTS [Abstract]
Impairment of real estate investments	1,860,000		305,000		428,000
Multi Family Residential [Member]
RECLASSIFICATIONS [Abstract]
Number of real estate properties classified as discontinued operations	2		3
Commercial Healthcare [Member]
RECLASSIFICATIONS [Abstract]
Number of real estate properties classified as discontinued operations			1
Commercial Industrial [Member]
RECLASSIFICATIONS [Abstract]
Number of real estate properties classified as discontinued operations	12
Commercial Industrial [Member] | Roseville, Minnesota [Member]
REAL ESTATE INVESTMENTS [Abstract]
Impairment of retail property	4,800,000
Number of impaired properties	1
Commercial Industrial [Member] | St. Louis Park, Minnesota [Member]
REAL ESTATE INVESTMENTS [Abstract]
Impairment of retail property	864,000
Number of impaired properties	1
Commercial Office [Member]
RECLASSIFICATIONS [Abstract]
Number of real estate properties classified as discontinued operations	3
REAL ESTATE INVESTMENTS [Abstract]
Number of real estate properties classified as held for sale	1
Commercial Office [Member] | Anoka, Minnesota [Member]
REAL ESTATE INVESTMENTS [Abstract]
Impairment of retail property	265,000
Number of impaired properties	1
Commercial Office [Member] | Bloomington, Minnesota [Member]
REAL ESTATE INVESTMENTS [Abstract]
Impairment of retail property	329,000
Number of impaired properties	1
Commercial Office [Member] | Clive, Iowa [Member]
REAL ESTATE INVESTMENTS [Abstract]
Impairment of retail property	402,000
Number of impaired properties	1
Commercial Office [Member] | Edina, Minnesota [Member]
REAL ESTATE INVESTMENTS [Abstract]
Impairment of retail property	835,000
Number of impaired properties	1
Commercial Office [Member] | Golden Valley, Minnesota [Member]
REAL ESTATE INVESTMENTS [Abstract]
Impairment of retail property	2,100,000
Number of impaired properties	1
Commercial Office [Member] | Various states [Member]
REAL ESTATE INVESTMENTS [Abstract]
Impairment of retail property	34,900,000
Number of impaired properties	8
Retail Property [Member]
RECLASSIFICATIONS [Abstract]
Number of real estate properties classified as discontinued operations	3		1
Retail Property [Member] | Kentwood, Michigan [Member]
REAL ESTATE INVESTMENTS [Abstract]
Impairment of retail property			$ 128,000
Number of impaired properties			1
Condominium Unit [Member]
RECLASSIFICATIONS [Abstract]
Number of real estate properties classified as discontinued operations			4

[1] (as revised)