ACQUISITIONS, DEVELOPMENTS PLACED IN SERVICE AND DISPOSITIONS, PROPERTY ACQUISITIONS (Details)		3 Months Ended
		Jul. 31, 2015 USD ($) Property	Jul. 31, 2014 USD ($) Property Unit
Business Acquisition [Line Items]
Transaction costs expensed during the period			$ 75,000
Acquisitions and development projects placed in service [Abstract]
Total acquisition cost			26,578,000
Form of consideration, cash			12,996,000
Form of consideration, other	[1]		13,582,000
Investment allocation, land			9,168,000
Investment allocation, building			17,145,000
Investment allocation, intangible assets			265,000
Goodwill, acquired during period		$ 0	852,000
Results of operations from acquired properties [Abstract]
Total revenue			362,000
Net income			$ 20,000
Office [Member]
Results of operations from acquired properties [Abstract]
Number of properties sold | Property		1	1
Multi-Family Residential [Member]
Acquisitions and development projects placed in service [Abstract]
Total acquisition cost			$ 18,280,000
Form of consideration, cash			6,111,000
Form of consideration, other	[1]		12,169,000
Investment allocation, land			870,000
Investment allocation, building			17,145,000
Investment allocation, intangible assets			$ 265,000
Multi-Family Residential [Member] | Homestead Garden - Rapid City, SD [Member]
Acquisitions and development projects placed in service [Abstract]
Date acquired	[2]		Jun. 02, 2014
Total acquisition cost	[2]		$ 15,000,000
Form of consideration, cash	[2]		5,092,000
Form of consideration, other	[1],[2]		9,908,000
Investment allocation, land	[2]		655,000
Investment allocation, building	[2]		14,139,000
Investment allocation, intangible assets	[2]		$ 206,000
Number of units | Unit	[2]		152
Goodwill, acquired during period			$ 852,000
Assumed debt			$ 9,900,000
Multi-Family Residential [Member] | Silver Springs - Rapid City, SD [Member]
Acquisitions and development projects placed in service [Abstract]
Date acquired			Jun. 02, 2014
Total acquisition cost			$ 3,280,000
Form of consideration, cash			1,019,000
Form of consideration, other	[1]		2,261,000
Investment allocation, land			215,000
Investment allocation, building			3,006,000
Investment allocation, intangible assets			$ 59,000
Number of units | Unit			52
Assumed debt			$ 2,300,000
Commercial Industrial [Member]
Results of operations from acquired properties [Abstract]
Number of properties sold | Property			1
Unimproved Land [Member]
Acquisitions and development projects placed in service [Abstract]
Total acquisition cost			$ 8,298,000
Form of consideration, cash			6,885,000
Form of consideration, other	[1]		1,413,000
Investment allocation, land			8,298,000
Investment allocation, building			0
Investment allocation, intangible assets			$ 0
Unimproved Land [Member] | Creekside Crossing - Bismarck, ND [Member]
Acquisitions and development projects placed in service [Abstract]
Date acquired			May 22, 2014
Total acquisition cost			$ 4,269,000
Form of consideration, cash			4,269,000
Form of consideration, other	[1]		0
Investment allocation, land			4,269,000
Investment allocation, building			0
Investment allocation, intangible assets			$ 0
Unimproved Land [Member] | PrairieCare Medical - Brooklyn Park, MN [Member]
Acquisitions and development projects placed in service [Abstract]
Date acquired			Jun. 05, 2014
Total acquisition cost			$ 2,616,000
Form of consideration, cash			2,616,000
Form of consideration, other	[1]		0
Investment allocation, land			2,616,000
Investment allocation, building			0
Investment allocation, intangible assets			$ 0
Unimproved Land [Member] | 71 France Phase I - Edina, MN [Member]
Acquisitions and development projects placed in service [Abstract]
Date acquired	[3]		Jun. 12, 2014
Total acquisition cost	[3]		$ 1,413,000
Form of consideration, cash	[3]		0
Form of consideration, other	[1],[3]		1,413,000
Investment allocation, land	[3]		1,413,000
Investment allocation, building	[3]		0
Investment allocation, intangible assets	[3]		$ 0
Interest held (in hundredths)			52.60%
JV partner contributions			$ 1,400,000

[1] Consists of assumed debt (Homestead Garden I: $9.9 million, Silver Springs: $2.3 million) and value of land contributed by the joint venture partner (71 France: $1.4 million).

[2] At acquisition, the Company adjusted the assumed debt to fair value and recognized approximately $852,000 of goodwill.

[3] Land was contributed to a joint venture in which the Company has an approximately 52.6% interest. The joint venture is consolidated in IRET's financial statements.