EARNINGS PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended
Jan. 31, 2015	Jan. 31, 2014	Jan. 31, 2015	Jan. 31, 2014
EARNINGS PER SHARE [Abstract]
Redemption basis			one-for-one
Period to hold the beneficial interest, minimum			1 year
NUMERATOR [Abstract]
Income from continuing operations - Investors Real Estate Trust	$ 8,371	$ 3,117	$ 13,334	$ 10,034
Income from discontinued operations - Investors Real Estate Trust	0	386	0	5,334
Net income attributable to Investors Real Estate Trust	8,371us-gaap_NetIncomeLoss	3,503us-gaap_NetIncomeLoss	13,334us-gaap_NetIncomeLoss	15,368us-gaap_NetIncomeLoss
Dividends to preferred shareholders	(2,879)us-gaap_DividendsPreferredStock	(2,879)us-gaap_DividendsPreferredStock	(8,636)us-gaap_DividendsPreferredStock	(8,636)us-gaap_DividendsPreferredStock
Numerator for basic earnings per share - net income available to common shareholders	5,492	624	4,698	6,732
Noncontrolling interests - Operating Partnership	657	130	618	1,406
Numerator for diluted earnings per share	$ 6,149	$ 754	$ 5,316	$ 8,138
DENOMINATOR [Abstract]
Denominator for basic earnings per share weighted average shares (in shares)	120,855	106,208	116,303	104,472
Effect of convertible operating partnership units (in shares)	14,461	21,819	17,334	21,830
Denominator for diluted earnings per share (in shares)	135,316	128,027	133,637	126,302
Earnings (loss) per common share from continuing operations - Investors Real Estate Trust - basic and diluted	$ 0.05	$ 0	$ 0.04	$ 0.01
Earnings per common share from discontinued operations - Investors Real Estate Trust - basic and diluted (in dollars per share)	$ 0	$ 0	$ 0	$ 0.05
NET INCOME (LOSS) PER COMMON SHARE - BASIC & DILUTED	$ 0.05us-gaap_EarningsPerShareBasicAndDiluted	$ 0us-gaap_EarningsPerShareBasicAndDiluted	$ 0.04us-gaap_EarningsPerShareBasicAndDiluted	$ 0.06us-gaap_EarningsPerShareBasicAndDiluted

The minimum period for which some limited partners have contractually agreed to hold the beneficial interest.

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The number of limited partners' units to be redeemed in exchange for a number of common shares upon exercise of the redemption option by the limited partners.

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Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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The amount of net income (loss) from continuing operations per each basic and diluted share of common stock or unit when the per share amount is the same for both basic and diluted shares.

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Amount of income (loss) from a disposal group, net of income tax, reported as a separate component of income before extraordinary items after deduction or consideration of the amount allocable to noncontrolling interests. Includes, net of tax, income (loss) from operations during the phase-out period, gain (loss) on disposal, provision (or any reversals of earlier provisions) for loss on disposal, and adjustments of a prior period gain (loss) on disposal.

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Per basic and diluted share amount, after tax, of income (loss) from the day-to-day business activities of the discontinued operation and gain (loss) from the disposal of the discontinued operation, when the per share amount is the same.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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Net Income or Loss Available to Common Stockholders plus adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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Amount after tax of income (loss) attributable to nonredeemable noncontrolling partner in an operating partnership.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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