Segment Reporting - Summary of Segment Revenues and Net Operating Income (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
SEGMENT REPORTING
Income from rental operations	$ 30,821		$ 30,270		$ 60,727	$ 60,102
Expenses from rental operations	14,100		14,851		29,799	30,059
Net operating income	16,721		15,419		30,928	30,043
Depreciation and amortization	5,246		5,353		10,498	10,891
Interest	4,224		4,582		8,574	9,298
Administration of REIT	1,085		971		2,247	2,082
Other (income)/expense	(231)		(308)		(2,015)	(839)
Net income	6,397	$ 5,227	4,821	$ 3,790	11,624	8,611
Residential
SEGMENT REPORTING
Income from rental operations	24,381		23,822		48,376	47,258
Expenses from rental operations	12,560		12,995		26,472	26,384
Net operating income	11,821		10,827		21,904	20,874
Commercial
SEGMENT REPORTING
Income from rental operations	6,440		6,448		12,351	12,844
Expenses from rental operations	1,540		1,856		3,327	3,675
Net operating income	$ 4,900		$ 4,592		$ 9,024	$ 9,169