INVESTMENT IN UNCONSOLIDATED VENTURES - Dispositions (Details) $ in Thousands					3 Months Ended								12 Months Ended
	Nov. 04, 2021 USD ($) property_unit	Jul. 28, 2021 USD ($) property_unit	Jul. 20, 2021 USD ($) property_unit	Apr. 20, 2021 USD ($) property_unit	Dec. 31, 2021 USD ($) property_unit	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2021 USD ($) property_unit	Dec. 31, 2020 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units | property_unit					2,576								2,576
BRT Share of Loss of Extinguishment of Debt					$ 673	$ 902	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 1,575	$ 0
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					273								273
Sales Price					$ 25,045								$ 25,045
BRT's Share of Gain on Sale													7,693
Unconsolidated joint ventures
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
BRT Share of Loss of Extinguishment of Debt													$ 9,401	$ 0
Unconsolidated joint ventures | Disposition of real estate properties | 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					1,108								1,108
Sales Price					$ 225,911								$ 225,911
BRT's Share of Gain on Sale													34,982
Partner's Share of Gain on Sale													49,002
BRT Share of Loss of Extinguishment of Debt													$ 4,581
Unconsolidated joint ventures | Disposition of real estate properties | Sale of Venture Interests
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units | property_unit					389								389
Sales Price					$ 10,540								$ 10,540
BRT's Share of Gain on Sale													$ 2,632
Unconsolidated joint ventures | Avenue Apts,Ocoee, FL | Disposition of real estate properties | 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			522
Sales Price			$ 107,661
BRT's Share of Gain on Sale			19,518
Partner's Share of Gain on Sale			20,150
BRT Share of Loss of Extinguishment of Debt			$ 4,474
Unconsolidated joint ventures | Parc at 980, Lawrenceville, GA | Disposition of real estate properties | 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		586
Sales Price		$ 118,250
BRT's Share of Gain on Sale		15,464
Partner's Share of Gain on Sale		28,852
BRT Share of Loss of Extinguishment of Debt		$ 107
Unconsolidated joint ventures | Anatole, Daytona Beach, FL | Disposition of real estate properties | Sale of Venture Interests
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units | property_unit				208
Sales Price				$ 7,540
BRT's Share of Gain on Sale				$ 2,244
Unconsolidated joint ventures | OPOP Tower and Lofts, St. Louis, MO | Disposition of real estate properties | Sale of Venture Interests
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units | property_unit	181
Sales Price	$ 3,000
BRT's Share of Gain on Sale	$ 388