ACQUISITIONS AND DISPOSITIONS (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Oct. 31, 2013		Oct. 31, 2012
Acquisitions and development projects placed in service [Abstract]
Land	$ 6,413		$ 5,985
Buildings	27,473		51,892
Intangible assets	893		813
Acquisition costs	34,779		58,690
Results of operations from acquired properties [Abstract]
Total revenue	573		2,929
Net income	(233)		(135)
Dispositions [Abstract]
Sales price	69,138		8,223
Book value and sales cost	62,497		5,543
Gain/(Loss)	6,641		2,680
Multi-Family Residential [Member]
Acquisitions and development projects placed in service [Abstract]
Land	1,492		4,715
Buildings	17,583		51,892
Intangible assets	525		813
Acquisition costs	19,600		57,420
Dispositions [Abstract]
Sales price			6,900
Book value and sales cost			4,094
Gain/(Loss)			2,806
Commercial Office [Member]
Dispositions [Abstract]
Sales price	12,950
Book value and sales cost	14,504
Gain/(Loss)	(1,554)
Commercial Industrial [Member]
Dispositions [Abstract]
Sales price	53,878
Book value and sales cost	45,573
Gain/(Loss)	8,305
Unimproved Land [Member]
Acquisitions and development projects placed in service [Abstract]
Land	3,809		1,270
Buildings	0		0
Intangible assets	0		0
Acquisition costs	3,809		1,270
Other Disposition [Member]
Dispositions [Abstract]
Sales price			698
Book value and sales cost			757
Gain/(Loss)			(59)
Alps Park - Rapid City, SD [Member] | Multi-Family Residential [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition	May 01, 2013
Land	287
Buildings	5,551
Intangible assets	362
Acquisition costs	6,200
Number of apartment units	71
API Building, Duluth, Minnesota [Member] | Commercial Industrial [Member]
Dispositions [Abstract]
Date Disposal	Sep. 24, 2013
Sales price	2,553
Book value and sales cost	1,488
Gain/(Loss)	1,065
Area of a real estate property (in square feet)	35,000
Bloomington Business Plaza, Bloomington, Minnesota [Member] | Commercial Office [Member]
Dispositions [Abstract]
Date Disposal	Sep. 12, 2013
Sales price	4,500
Book value and sales cost	7,339
Gain/(Loss)	(2,839)
Area of a real estate property (in square feet)	121,669
Bodycote Industrial Building - Eden Prairie, MN [Member] | Commercial Industrial [Member]
Dispositions [Abstract]
Date Disposal	May 13, 2013
Sales price	3,150
Book value and sales cost	1,375
Gain/(Loss)	1,775
Area of a real estate property (in square feet)	41,880
Brooklyn Park 7401 Boone Avenue, Brooklyn Park, Minnesota [Member] | Commercial Industrial [Member]
Dispositions [Abstract]
Date Disposal	Sep. 12, 2013
Sales price	12,800
Book value and sales cost	12,181
Gain/(Loss)	619
Area of a real estate property (in square feet)	322,751
Chateau II - Minot, ND [Member] | Unimproved Land [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition	May 21, 2013
Land	179
Buildings	0
Intangible assets	0
Acquisition costs	179
Cedar Lake Business Center, St. Louis Park, Minnesota [Member] | Commercial Industrial [Member]
Dispositions [Abstract]
Date Disposal	Sep. 12, 2013
Sales price	2,550
Book value and sales cost	2,607
Gain/(Loss)	(57)
Area of a real estate property (in square feet)	50,400
Colony Lincoln, NE [Member] | Multi-Family Residential [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition			Jun. 04, 2012
Land			1,515
Buildings			15,731
Intangible assets			254
Acquisition costs			17,500
Number of apartment units			232
Cypress Court - St. Cloud, MN [Member] | Unimproved Land [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition			Aug. 10, 2012
Land			447
Buildings			0
Intangible assets			0
Acquisition costs			447
Dixon Avenue Industrial Park, Des Moines, Iowa [Member] | Commercial Industrial [Member]
Dispositions [Abstract]
Date Disposal	Oct. 31, 2013
Sales price	14,675
Book value and sales cost	10,328
Gain/(Loss)	4,347
Area of a real estate property (in square feet)	606,006
Eagan Community- Eagan, MN [Member] | Commercial Retail [Member]
Dispositions [Abstract]
Date Disposal	May 14, 2013
Sales price	2,310
Book value and sales cost	2,420
Gain/(Loss)	(110)
Area of a real estate property (in square feet)	23,187
Fargo 1320 45th St. N - Fargo, ND [Member] | Commercial Industrial [Member]
Dispositions [Abstract]
Date Disposal	May 13, 2013
Sales price	4,700
Book value and sales cost	4,100
Gain/(Loss)	600
Area of a real estate property (in square feet)	42,244
Georgetown Square Condominiums 3 and 4 [Member] | Other Disposition [Member]
Dispositions [Abstract]
Date Disposal			Aug. 02, 2012
Sales price			368
Book value and sales cost			421
Gain/(Loss)			(53)
Georgetown Square Condominiums 5 and 6 [Member] | Other Disposition [Member]
Dispositions [Abstract]
Date Disposal			Jun. 21, 2012
Sales price			330
Book value and sales cost			336
Gain/(Loss)			(6)
Jamestown Unimproved - Jamestown, ND [Member] | Unimproved Land [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition	Aug. 09, 2013
Land	700
Buildings	0
Intangible assets	0
Acquisition costs	700
Kentwood Thomasville Kentwood, MI [Member] | Commercial Retail [Member]
Dispositions [Abstract]
Date Disposal			Jun. 20, 2012
Sales price			625
Book value and sales cost			692
Gain/(Loss)			(67)
Area of a real estate property (in square feet)			16,080
Lakeside Village Lincoln, NE [Member] | Multi-Family Residential [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition			Jun. 04, 2012
Land			1,215
Buildings			15,837
Intangible assets			198
Acquisition costs			17,250
Number of apartment units			208
Legends at Heritage Place - Sartell, MN [Member] | Commercial Healthcare [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition	Oct. 31, 2013
Land	1,112
Buildings	9,890
Intangible assets	368
Acquisition costs	11,370
Area Of Real Estate Property Acquisitions (in square feet)	98,174
Legends at Heritage Place - Sartell, MN [Member] | Unimproved Land [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition	Oct. 31, 2013
Land	1,030
Buildings	0
Intangible assets	0
Acquisition costs	1,030
Lighthouse - Duluth, MN [Member] | Commercial Industrial [Member]
Dispositions [Abstract]
Date Disposal	Oct. 08, 2013
Sales price	1,825
Book value and sales cost	1,547
Gain/(Loss)	278
Area of a real estate property (in square feet)	59,292
Metal Improvement - New Brighton, MN [Member] | Commercial Industrial [Member]
Dispositions [Abstract]
Date Disposal	May 13, 2013
Sales price	2,350
Book value and sales cost	1,949
Gain/(Loss)	401
Area of a real estate property (in square feet)	49,620
Nicollet VII, Burnsville, Minnesota [Member] | Commercial Office [Member]
Dispositions [Abstract]
Date Disposal	Sep. 12, 2013
Sales price	7,290
Book value and sales cost	6,001
Gain/(Loss)	1,289
Area of a real estate property (in square feet)	118,125
Pillsbury Business Center, Bloomington, Minnesota [Member] | Commercial Office [Member]
Dispositions [Abstract]
Date Disposal	Sep. 12, 2013
Sales price	1,160
Book value and sales cost	1,164
Gain/(Loss)	(4)
Area of a real estate property (in square feet)	42,929
Pinecone Villas - Sartell, MN [Member] | Multi-Family Residential [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition	Oct. 31, 2013
Land	629
Buildings	2,139
Intangible assets	32
Acquisition costs	2,800
Number of apartment units	24
Ponds at Heritage Place - Sartell, MN [Member] | Multi-Family Residential [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition			Oct. 10, 2012
Land			395
Buildings			4,564
Intangible assets			61
Acquisition costs			5,020
Number of apartment units			58
Prairiewood Meadows - Fargo, ND [Member] | Multi-Family Residential [Member]
Dispositions [Abstract]
Date Disposal			Sep. 27, 2012
Sales price			3,450
Book value and sales cost			2,846
Gain/(Loss)			604
iret_ Number Of Apartment Units Dispositions			85
RED 20 - Minneapolis, MN [Member] | Unimproved Land [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition	Aug. 20, 2013	[1]
Land	1,900	[1]
Buildings	0	[1]
Intangible assets	0	[1]
Acquisition costs	1,900	[1]
Roseville 2929 Long Lake Road - Roseville, MN [Member] | Commercial Industrial [Member]
Dispositions [Abstract]
Date Disposal	May 13, 2013
Sales price	9,275
Book value and sales cost	9,998
Gain/(Loss)	(723)
Area of a real estate property (in square feet)	172,057
Southpoint - Grand Forks, ND [Member] | Multi-Family Residential [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition	Sep. 05, 2013
Land	576
Buildings	9,893
Intangible assets	131
Acquisition costs	10,600
Number of apartment units	96
Terrace on the Green - Fargo, ND [Member] | Multi-Family Residential [Member]
Dispositions [Abstract]
Date Disposal			Sep. 27, 2012
Sales price			3,450
Book value and sales cost			1,248
Gain/(Loss)			2,202
iret_ Number Of Apartment Units Dispositions			116
Villa West Topeka, KS [Member] | Multi-Family Residential [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition			May 08, 2012
Land			1,590
Buildings			15,760
Intangible assets			300
Acquisition costs			17,650
Number of apartment units			308
University Commons - Williston, ND [Member] | Unimproved Land [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition			Aug. 01, 2012
Land			823
Buildings			0
Intangible assets			0
Acquisition costs			823
Development Projects Placed in Service [Member]
Acquisitions and development projects placed in service [Abstract]
Land	0	[2]	0
Buildings	8,822	[2]	11,477
Intangible assets	0	[2]	0
Acquisition costs	8,822	[2]	11,477
Development Projects Placed in Service [Member] | Quarry Ridge II Rochester, MN [Member] | Multi-Family Residential [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition			Jun. 29, 2012	[3]
Land			0	[3]
Buildings			4,591	[3]
Intangible assets			0	[3]
Acquisition costs			4,591	[3]
Number of apartment units			159	[3]
Development Projects Placed in Service [Member] | The Landing at Southgate, Minot, ND [Member] | Multi-Family Residential [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition	Sep. 04, 2013	[2],[4]
Land	0	[2],[4]
Buildings	8,822	[2],[4]
Intangible assets	0	[2],[4]
Acquisition costs	8,822	[2],[4]
Number of apartment units	108	[2],[4]
Development Projects Placed in Service [Member] | Williston Garden Buildings 3 and 4 Williston, ND [Member] | Multi-Family Residential [Member]
Acquisitions and development projects placed in service [Abstract]
Date Acquisition			Jul. 31, 2012	[5]
Land			0	[5]
Buildings			6,886	[5]
Intangible assets			0	[5]
Acquisition costs			$ 6,886	[5]
Number of apartment units			73	[4]

[1] Land is owned by a joint venture in which the Company has an approximately 59% interest. The joint venture is consolidated in IRET's financial statements.

[2] Development projects that are placed in service in phases are excluded from this table until the entire project has been placed in service. See Note 6 for additional information on the River Ridge and Cypress Court projects, which were partially placed in service during the three months ended October 31, 2013.

[3] Development property placed in service June 29, 2012. Additional costs paid in fiscal years 2012 and 2011, and land acquired in fiscal year 2007, totaled $13.0 million, for a total project cost at October 31, 2012 of $17.6 million.

[4] Development property placed in service September 4, 2013. Additional costs paid in fiscal year 2013 totaled $6.3 million, for a total project cost at October 31, 2013 of $15.1 million. The project is owned by a joint venture entity in which the Company has a 51% interest.

[5] Development property placed in service July 31, 2012. Buildings 1 and 2 were placed in service in fiscal year 2012. Additional costs paid in fiscal year 2012 totaled $12.0 million, for a total project cost at October 31, 2012 of $18.9 million. The project is owned by a joint venture entity in which the Company has a 60% interest.