EARNINGS PER SHARE (Details) $ / shares in Units, $ in Thousands	2 Months Ended	3 Months Ended										8 Months Ended		12 Months Ended
	Dec. 31, 2018 USD ($) $ / shares	Oct. 31, 2018 USD ($) $ / shares	Jul. 31, 2018 USD ($) $ / shares	Apr. 30, 2018 USD ($) $ / shares	Jan. 31, 2018 USD ($) $ / shares	Oct. 31, 2017 USD ($) $ / shares	Jul. 31, 2017 USD ($) $ / shares	Apr. 30, 2017 USD ($) $ / shares	Jan. 31, 2017 USD ($) $ / shares	Oct. 31, 2016 USD ($) $ / shares	Jul. 31, 2016 USD ($) $ / shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) $ / shares	Apr. 30, 2018 USD ($) $ / shares shares	Apr. 30, 2017 USD ($) $ / shares shares	Apr. 30, 2016 USD ($) $ / shares shares
Earnings Per Share [Abstract]
Ratio of units exchanged for shares												1
Antidilutive excluded from computation of earnings per share | shares												25,300
Net Income (Loss) Attributable to Parent [Abstract]
Income (loss) from continuing operations – controlling interests												$ (4,908)		$ (30,266)	$ (24,473)	$ 11,553
Income (loss) from discontinued operations – controlling interests												510		147,054	67,820	60,453
Net income (loss) attributable to controlling interests	$ (2,756)	$ (4,558)	$ 2,916	$ (20,874)	$ 136,105	$ 12,821	$ (11,264)	$ 30,280	$ 23,110	$ 11,600	$ (21,643)	(4,398)	$ 127,414	116,788	43,347	72,006
Dividends to preferred shareholders												(4,547)		(8,569)	(10,546)	(11,514)
Redemption of preferred shares												0	(3,657)	(3,657)	(1,435)	0
NET INCOME (LOSS) AVAILABLE TO COMMON SHAREHOLDERS	$ (3,892)	$ (6,264)	$ 1,211	$ (22,579)	$ 134,331	$ 6,360	$ (13,550)	$ 27,994	$ 19,172	$ 8,722	$ (24,522)	(8,945)	117,461	104,562	31,366	60,492
Noncontrolling interests – Operating Partnership												(1,032)	$ 14,222	12,702	4,059	7,032
Numerator for diluted earnings per share												$ (9,977)		$ 117,264	$ 35,425	$ 67,524
DENOMINATOR
Denominator for basic earnings per share weighted average shares (in shares) | shares												11,937,000		119,977,000	121,169,000	123,094,000
Effect of convertible operating partnership units (in shares) | shares												1,387,000		14,617,000	16,130,000	14,278,000
Denominator for diluted earnings per share (in shares) | shares												13,324,000		134,594,000	137,299,000	137,372,000
Earnings (loss) per common share from continuing operations – Investors Real Estate Trust – basic and diluted (in dollars per share) | $ / shares												$ (0.79)	$ (1.41)	$ (3.54)	$ (3.01)	$ 0.00
Earnings (loss) per common share from discontinued operations – basic and diluted (in dollars per share) | $ / shares												0.04	11.19	12.25	5.59	4.91
NET EARNINGS (LOSS) PER COMMON SHARE – BASIC & DILUTED (in dollars per share) | $ / shares	$ (0.33)	$ (0.52)	$ 0.10	$ (1.89)	$ 11.22	$ 0.53	$ (1.12)	$ 2.33	$ 1.58	$ 0.72	$ (2.02)	$ (0.75)	$ 9.78	$ 8.71	$ 2.58	$ 4.91