Real Estate Investments (Operating Results Included in the Company's Historical Consolidated Statement of Operations for Properties Acquired During the Reported Periods) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2018 USD ($)
Real Estate [Abstract]
Revenues	$ 145
Net income attributable to Retail Opportunity Investments Corp.	$ 78

Asset Acquisition, Net Income (Loss) Attributable to Parent, Total

No definition available.

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