Consolidated Statement of Partners' Capital (Parentheticals) - $ / shares	3 Months Ended
Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018
Retail Opportunity Investments Partnership L.P.
Cash distributions per unit (in dollars per share)	$ 0.1970	$ 0.1970	$ 0.1970	$ 0.1950	$ 0.1950	$ 0.1950

Per unit of ownership amount of cash distributions paid to unit-holder of a limited partnership (LP).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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