Investment in Unconsolidated Ventures - Income Statement Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenues:
Total revenues	$ 7,313	$ 6,422	$ 21,053	$ 20,839
Expenses:
Real estate operating expenses	3,289	2,741	9,351	9,242
Interest expense	1,731	1,870	5,400	5,865
Depreciation	1,777	1,373	5,147	4,348
Total expenses	13,169	8,414	32,594	26,910
Total revenues less total expenses	(5,856)	(1,992)	(11,541)	(6,071)
Loss on extinguishment of debt	0	(1,387)	0	(1,387)
Consolidation of investment in limited partnership	34	799	97	877
BRT equity in loss from joint ventures	(7,484)	3,272	(16,561)	(5,292)
Unconsolidated joint ventures
Revenues:
Rental and other revenue	32,341	31,273	94,726	87,076
Total revenues	32,341	31,273	94,726	87,076
Expenses:
Real estate operating expenses	16,092	15,212	45,298	42,612
Interest expense	8,663	9,202	26,186	26,027
Depreciation	10,411	9,901	31,184	29,121
Total expenses	35,166	34,315	102,668	97,760
Total revenues less total expenses	(2,825)	(3,042)	(7,942)	(10,684)
Loss on extinguishment of debt	0	(379)	0	(379)
Gain on insurance recoveries	427	0	765	517
Consolidation of investment in limited partnership	(2,398)	(3,421)	(7,177)	(10,546)
BRT equity in loss from joint ventures	$ (1,529)	$ (2,390)	$ (4,731)	$ (6,676)