Investment in Unconsolidated Ventures - Balance Sheet Information (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023	Dec. 31, 2022
ASSETS
Real estate properties, net of accumulated depreciation of $72,863 and $69,970	$ 631,001	$ 635,836
Cash and cash equivalents	21,252	23,512	$ 15,252
Other assets	13,690	15,741
Total Assets	699,485	709,963
Liabilities:
Mortgages payable, net of deferred costs of $1,061 and $1,135	421,835	422,427
Accounts payable and accrued liabilities	19,888	21,948
Total Liabilities	478,871	481,518
Commitments and contingencies
Equity:
Total unconsolidated joint venture equity	220,614	228,445	$ 243,334	$ 250,070
Total Liabilities and Equity	699,485	709,963
Real estate accumulated depreciation	86,934	80,499
Deferred costs	4,049	4,266
Asset under Construction
ASSETS
Real estate properties, net of accumulated depreciation of $72,863 and $69,970	12,715	46,508
Unconsolidated Joint Ventures
ASSETS
Real estate properties, net of accumulated depreciation of $72,863 and $69,970	311,569	275,874
Cash and cash equivalents	5,769	6,447
Other assets	17,677	54,715
Total Assets	335,015	337,036
Liabilities:
Mortgages payable, net of deferred costs of $1,061 and $1,135	249,245	246,966
Accounts payable and accrued liabilities	7,920	8,751
Total Liabilities	257,165	255,717
Commitments and contingencies
Equity:
Total unconsolidated joint venture equity	77,850	81,319
Total Liabilities and Equity	335,015	337,036
BRT's interest in joint venture equity	32,953	34,242
Unconsolidated Joint Ventures
Equity:
Real estate accumulated depreciation	72,863	69,970
Unconsolidated Joint Ventures | Mortgages payable
Equity:
Deferred costs	$ 1,061	$ 1,135