Segment Reporting - Summary of Segment Revenues and Net Operating Income (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
SEGMENT REPORTING
Income from rental operations	$ 30,173			$ 29,055			$ 90,275	$ 86,802
Expenses from rental operations	15,380			14,200			45,439	42,655
Net operating income	14,793			14,855			44,836	44,147
Depreciation and amortization	5,322			5,274			16,213	15,907
Interest	4,521			4,557			13,819	13,632
Administration of REIT	969			1,460			3,051	3,703
Other (income)/expense	511			(3,520)			(328)	(6,416)
Net income	3,470	$ 4,821	$ 3,790	7,084	$ 4,979	$ 5,258	12,081	17,321
Residential
SEGMENT REPORTING
Income from rental operations	23,662			22,439			70,920	66,683
Expenses from rental operations	13,570			12,247			39,954	37,093
Net operating income	10,092			10,192			30,966	29,590
Commercial
SEGMENT REPORTING
Income from rental operations	6,511			6,616			19,355	20,119
Expenses from rental operations	1,810			1,953			5,485	5,562
Net operating income	$ 4,701			$ 4,663			$ 13,870	$ 14,557