Operating Segments - Profit by Reportable Segment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Segment Reporting Information [Line Items]
Revenues	$ 11,103	$ 14,741	$ 22,931	$ 27,871
Total profit from segments	(8,771)	1,491	(11,773)	(1,747)
Operating segments
Segment Reporting Information [Line Items]
Total profit from segments	5,136	5,755	9,665	10,888
Operating segments | Multifamily Segment
Segment Reporting Information [Line Items]
Revenues	3,529	3,702	7,365	7,258
Operating expenses	(2,111)	(2,108)	(4,234)	(4,053)
Profit from segment	1,418	1,594	3,131	3,205
Operating segments | Commercial Segment
Segment Reporting Information [Line Items]
Revenues	6,665	7,863	13,190	15,749
Operating expenses	(2,947)	(3,702)	(6,656)	(8,066)
Profit from segment	$ 3,718	$ 4,161	$ 6,534	$ 7,683