NONCONTROLLING INTERESTS (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Apr. 30, 2018	Apr. 30, 2017
Noncontrolling Interest [Line Items]
Noncontrolling interests – consolidated real estate entities	$ 6,747	$ 8,888	$ 9,204
IRET - 71 France, LLC
Noncontrolling Interest [Line Items]
Noncontrolling interests – consolidated real estate entities	5,918	6,606	7,427
IRET - Cypress Court Apartments, LLC
Noncontrolling Interest [Line Items]
Noncontrolling interests – consolidated real estate entities	829	890	979
IRET - Williston Garden Apartments, LLC
Noncontrolling Interest [Line Items]
Noncontrolling interests – consolidated real estate entities	0	1,635	1,057
IRET - WRH 1, LLC
Noncontrolling Interest [Line Items]
Noncontrolling interests – consolidated real estate entities	0	(467)	(619)
WRH Holding, LLC
Noncontrolling Interest [Line Items]
Noncontrolling interests – consolidated real estate entities	$ 0	$ 224	$ 360