Investment in Unconsolidated Ventures - Balance Sheet Information (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
ASSETS
Real estate properties, net of accumulated depreciation of $62,273 and $66,945	$ 647,476	$ 651,603
Cash and cash equivalents	15,252	20,281	$ 29,688
Other assets	14,980	16,786
Total Assets	719,701	732,118
Liabilities:
Mortgages payable, net of deferred costs of $1,367 and $1,421	423,820	403,792
Accounts payable and accrued liabilities	15,419	22,631
Total Liabilities	476,367	482,048
Commitments and contingencies
Equity:
Total unconsolidated joint venture equity	243,334	250,070	$ 214,202	$ 202,951
Total Liabilities and Equity	719,701	732,118
Deferred costs	4,927	4,941
Unconsolidated Joint Ventures
ASSETS
Real estate properties, net of accumulated depreciation of $62,273 and $66,945	282,329	318,304
Cash and cash equivalents	6,909	6,591
Other assets	37,563	35,372
Total Assets	360,771	360,267
Liabilities:
Mortgages payable, net of deferred costs of $1,367 and $1,421	259,482	255,261
Accounts payable and accrued liabilities	5,684	8,222
Total Liabilities	265,166	263,483
Commitments and contingencies
Equity:
Total unconsolidated joint venture equity	95,605	96,784
Total Liabilities and Equity	360,771	360,267
BRT's interest in joint venture equity	41,163	42,576
Unconsolidated Joint Ventures
ASSETS
Real estate property held for sale	33,970	0
Equity:
Real estate properties, net of accumulated depreciation	62,273	66,945
Unconsolidated Joint Ventures | Mortgages payable
Equity:
Deferred costs	$ 1,367	$ 1,421