Quarterly Financial Information (unaudited) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
QUARTERLY FINANCIAL INFORMATION (unaudited)
Income from rental operations	$ 27,441	$ 26,888	$ 27,046	$ 26,688	$ 26,117	$ 24,688	$ 23,552	$ 22,825	$ 108,063	$ 97,182	$ 70,936
Net income	4,254	2,523	2,706	3,374	1,526	2,087	4,596	3,178	12,857	11,384	9,303
Net income attributable to Sterling Real Estate Trust	$ 1,428	$ 885	$ 839	$ 1,273	$ 748	$ 1,078	$ 1,511	$ 952	$ 4,425	$ 4,286	$ 2,579
Net income per common share, basic and diluted	$ 0.17	$ 0.11	$ 0.11	$ 0.17	$ 0.10	$ 0.14	$ 0.20	$ 0.15	$ 0.56	$ 0.59	$ 0.47
Weighted average common shares outstanding	8,003,000	7,891,000	7,789,000	7,690,000	7,588	7,543	7,436	6,308