EQUITY AND MEZZANINE EQUITY - Narrative (Details)		3 Months Ended
	Sep. 01, 2021 USD ($) $ / shares	Mar. 31, 2023 USD ($) $ / shares shares	Mar. 31, 2022 USD ($) apartmentCommunity shares	Dec. 31, 2022 USD ($) $ / shares shares	Mar. 10, 2022 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Noncontrolling interests , operating partnership, outstanding (in shares) | shares		967,000		971,000
Noncontrolling interests , operating partnership, issued (in shares) | shares			209,000
Preferred shares, shares issued (in shares) | shares		3,881,000		3,881,000
Preferred shares liquidation preference		$ 97,036,000		$ 97,036,000
Common stock outstanding (in shares) | shares		15,032,000		15,020,000
Sale of common shares, net			$ 31,684,000
Stock repurchase program, authorized amount					$ 50,000,000
Remaining authorized repurchase amount		$ 19,900,000
Preferred shares of beneficial interest, shares outstanding (in shares) | shares		3,881,000		3,881,000
Preferred shares, liquidation preference (in dollars per share) | $ / shares		$ 25		$ 25
Preferred units, shares issued (in shares) | shares		166,000		166,000
Preferred units, par value (in dollars per share) | $ / shares		$ 100		$ 100
Preferred units, liquidation preference		$ 16,560,000		$ 16,560,000
2022 Acquisitions, Three Apartment Communities
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of apartment communities acquired | apartmentCommunity			3
Series E Preferred Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred shares, shares issued (in shares) | shares		1,700,000		1,800,000
Preferred units, par value (in dollars per share) | $ / shares	$ 100
Preferred shares, dividend rate	0.03875%
Preferred units, conversion ratio	1.2048
Preferred shares liquidation preference	$ 174,500,000
Series C Preferred Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred shares, dividend rate		6.625%
Preferred shares liquidation preference		$ 97,000,000
Preferred shares of beneficial interest, shares outstanding (in shares) | shares		3,900,000		3,900,000
Preferred shares, liquidation preference (in dollars per share) | $ / shares		$ 25.00
Preferred shares, annual distribution accrual rate (in dollars per share) | $ / shares		$ 1.65625
Series D Preferred Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred units, shares issued (in shares) | shares		165,600		165,600
Preferred units, par value (in dollars per share) | $ / shares		$ 100
Distribution rate		3.862%
Units converted, ratio		1.37931
Preferred units, liquidation preference		$ 16,600,000
At-The-Market Offering
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate gross sales price of common shares, authorized amount			$ 250,000,000
Aggregate gross sales price of common shares, remaining authorized amount		$ 126,600,000
2015 Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards issued (in shares) | shares		11,877	18,759
Sale of common shares, net		$ 1,100,000	$ 1,500,000