Document and Entity Information - USD ($)	12 Months Ended
	Apr. 30, 2018	Jun. 20, 2018	Oct. 31, 2017
Document and Entity Information [Abstract]
Entity Registrant Name	INVESTORS REAL ESTATE TRUST
Entity Central Index Key	0000798359
Current Fiscal Year End Date	--04-30
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 695,861,225
Entity Common Stock, Shares Outstanding		119,406,963
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	FY
Document Type	10-K
Amendment Flag	false
Document Period End Date	Apr. 30, 2018