INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Income Or Loss From Unconsolidated Joint Ventures) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Investments in Unconsolidated Joint Ventures
Loss from Unconsolidated Joint Venture Investments	$ (589)	$ (502)	$ (1,247)	$ (1,520)
Hiren Boston, LLC
Investments in Unconsolidated Joint Ventures
Loss from Unconsolidated Joint Venture Investments	(354)	(477)	(689)	(880)
SB Partners, LLC
Investments in Unconsolidated Joint Ventures
Loss from Unconsolidated Joint Venture Investments	(50)	0	(50)	(600)
SB Partners Three, LLC
Investments in Unconsolidated Joint Ventures
Loss from Unconsolidated Joint Venture Investments	$ (185)	$ (25)	$ (508)	$ (40)

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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