ACQUISITIONS, DISPOSITIONS AND IMPAIRMENT CHARGES - Schedule of Subsequent Property Dispositions (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($) property_unit property_Unit	Dec. 31, 2018 USD ($) property_unit
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units | property_Unit	1,880
Non-Controlling Partner's Share of Gain on Sale	$ 894
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	2
Sales Price	$ 34,032	$ 920
Loss from discontinued operations	$ 10,618	$ 863
Disposition of real estate properties | Joint ventures
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units | property_unit		1,851
Sales Price		$ 241,100
Loss from discontinued operations		71,056
Non-Controlling Partner's Share of Gain on Sale		$ 33,187
Disposition of real estate properties | Indianapolis, IN | Joint ventures
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units | property_unit	400
Sales Price	$ 36,500
Loss from discontinued operations	16,898
BRT share of gain	$ 9,933
Disposition of real estate properties | Valley, AL | Joint ventures
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units | property_unit		618
Sales Price		$ 51,000
Loss from discontinued operations		9,712
Non-Controlling Partner's Share of Gain on Sale		$ 4,547
Disposition of real estate properties | North Charleston, SC | Joint ventures
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units | property_unit		271
Sales Price		$ 51,650
Loss from discontinued operations		11,920
Non-Controlling Partner's Share of Gain on Sale		$ 5,970
Disposition of real estate properties | Houston, TX
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units | property_unit	384
Sales Price	$ 33,200
Loss from discontinued operations	9,938
Non-Controlling Partner's Share of Gain on Sale	$ 894
Disposition of real estate properties | Palm Beach Gardens, FL | Joint ventures
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units | property_unit		542
Sales Price		$ 97,250
Loss from discontinued operations		41,831
Non-Controlling Partner's Share of Gain on Sale		$ 20,593
Disposition of real estate properties | Lake Saint Louis, MO | Joint ventures
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
No. of Units | property_unit		420
Sales Price		$ 41,200
Loss from discontinued operations		7,593
Non-Controlling Partner's Share of Gain on Sale		$ 2,077