SEGMENTS - Revenues and Net Operating Income for Reportable Segments (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) segment apartmentCommunity	Sep. 30, 2022 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment			1
Segment revenues and net operating income [Abstract]
Revenue	$ 64,568,000	$ 65,438,000	$ 197,241,000	$ 188,868,000
Property operating expenses, including real estate taxes	26,745,000	27,329,000	80,714,000	79,418,000
Net operating income	37,823,000	38,109,000	116,527,000	109,450,000
Property management	(2,197,000)	(2,563,000)	(7,012,000)	(7,537,000)
Casualty loss	(937,000)	(276,000)	(1,242,000)	(1,256,000)
Depreciation and amortization	(24,697,000)	(23,720,000)	(75,061,000)	(79,489,000)
General and administrative expenses	(3,832,000)	(4,519,000)	(15,717,000)	(14,240,000)
Gain on sale of real estate and other investments	11,235,000	0	71,327,000	27,000
Loss on litigation settlement	0	0	(2,864,000)	0
Interest expense	(8,556,000)	(7,871,000)	(27,516,000)	(23,147,000)
Interest and other income	330,000	70,000	674,000	1,116,000
Net income (loss)	9,169,000	(770,000)	$ 59,116,000	(15,076,000)
Disposed of by Sale | 2023 Year To Date Disposals
Segment Reporting Information [Line Items]
Number of properties sold | apartmentCommunity			13
Multifamily
Segment revenues and net operating income [Abstract]
Revenue	61,505,000	57,057,000	$ 182,893,000	164,823,000
Property operating expenses, including real estate taxes	25,375,000	23,339,000	73,917,000	67,747,000
Net operating income	36,130,000	33,718,000	108,976,000	97,076,000
All Other
Segment revenues and net operating income [Abstract]
Revenue	3,063,000	8,381,000	14,348,000	24,045,000
Property operating expenses, including real estate taxes	1,370,000	3,990,000	6,797,000	11,671,000
Net operating income	$ 1,693,000	$ 4,391,000	$ 7,551,000	$ 12,374,000