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INVESTMENT IN UNCONSOLIDATED VENTURES - Dispositions (Details) $ in Thousands		2 Months Ended	3 Months Ended								12 Months Ended
	Feb. 02, 2021 USD ($)	May 31, 2021 USD ($)	Dec. 31, 2020 USD ($) property_Unit property_unit	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($) refinancing	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2020 USD ($) property_Unit property_unit	Dec. 31, 2019 USD ($) refinancing	Mar. 03, 2021 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units \| property_Unit			1,880								1,880
Non-Controlling Partner's Share of Gain on Sale											$ 894
Gain on sale of real estate							$ 680	$ 9,938	$ 0	$ 0	0	$ 10,618
Revenues			$ 7,049	$ 7,313	$ 6,816	$ 6,924	6,922	6,422	7,287	7,130	28,102	27,761
Interest expense			1,700	1,731	1,809	1,860	1,931	1,870	2,049	1,946	7,100	7,796
Depreciation			$ 1,595	$ 1,777	$ 1,809	$ 1,561	$ 1,568	$ 1,373	$ 1,428	$ 1,547	$ 6,742	$ 5,916
Disposition of real estate properties
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units \| property_unit			385								385
Sales Price			$ 34,032								$ 34,032
Loss from discontinued operations											$ 10,618
Indianapolis, IN \| Disposition of real estate properties
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units \| refinancing							400					400
Sales Price							$ 36,500					$ 36,500
Loss from discontinued operations												16,898
Non-Controlling Partner's Share of Gain on Sale												9,932
Unconsolidated joint ventures
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units \| property_Unit			9,162								9,162
Gain on sale of real estate											$ 0	16,899
Revenues											127,058	118,177
Interest expense											34,918	35,023
Depreciation											41,657	$ 39,218
Unconsolidated joint ventures \| Daytona Beach, FL \| Disposition of real estate properties \| Subsequent Event
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sales Price	$ 7,400
Ownership Percentage	80.00%
Unconsolidated joint ventures \| Kendall Manor - Houston, Texas \| Disposition of real estate properties
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Sales Price													$ 24,500
Revenues											2,900
Operating expenses											1,900
Interest expense											675
Depreciation											$ 848
Unconsolidated joint ventures \| Kendall Manor - Houston, Texas \| Disposition of real estate properties \| Forecast
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Gain on sale of real estate		$ 7,500