Consolidated Statements of Operations and Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues
Base rents	$ 223,797	$ 210,564	$ 183,330
Recoveries from tenants	65,804	58,818	51,454
Other income	6,197	3,878	2,405
Total revenues	295,798	273,260	237,189
Operating expenses
Property operating	43,851	39,151	32,201
Property taxes	32,349	29,663	25,058
Depreciation and amortization	100,838	96,256	88,359
General and administrative expenses	14,918	14,103	13,120
Acquisition transaction costs	0	4	824
Other expense	478	418	456
Total operating expenses	192,434	179,595	160,018
Gain on sale of real estate	5,890	0	0
Operating income	109,254	93,665	77,171
Non-operating expenses
Interest expense and other finance expenses	(62,113)	(50,977)	(40,741)
Net income	47,141	42,688	36,430
Net income attributable to non-controlling interests	(4,405)	(4,211)	(3,676)
Net Income Attributable to Retail Opportunity Investments Corp.	$ 42,736	$ 38,477	$ 32,754
Earnings per share/unit - basic and diluted (in usd per share)	$ 0.38	$ 0.35	$ 0.31
Dividends per share (in dollars per share)	$ 0.78	$ 0.75	$ 0.72
Comprehensive income:
Net income	$ 47,141	$ 42,688	$ 36,430
Unrealized swap derivative gain arising during the period	1,648	3,665	541
Reclassification adjustment for amortization of interest expense included in net income	57	1,920	2,473
Other comprehensive income	1,705	5,585	3,014
Comprehensive income	48,846	48,273	39,444
Comprehensive income attributable to non-controlling interests	(4,405)	(4,211)	(3,676)
Comprehensive income attributable to Retail Opportunity Investments Corp.	44,441	44,062	35,768
Retail Opportunity Investments Partnership L.P.
Revenues
Base rents	223,797	210,564	183,330
Recoveries from tenants	65,804	58,818	51,454
Other income	6,197	3,878	2,405
Total revenues	295,798	273,260	237,189
Operating expenses
Property operating	43,851	39,151	32,201
Property taxes	32,349	29,663	25,058
Depreciation and amortization	100,838	96,256	88,359
General and administrative expenses	14,918	14,103	13,120
Acquisition transaction costs	0	4	824
Other expense	478	418	456
Total operating expenses	192,434	179,595	160,018
Gain on sale of real estate	5,890	0	0
Operating income	109,254	93,665	77,171
Non-operating expenses
Interest expense and other finance expenses	(62,113)	(50,977)	(40,741)
Net income	$ 47,141	$ 42,688	$ 36,430
Earnings per share/unit - basic and diluted (in usd per share)	$ 0.38	$ 0.35	$ 0.31
Dividends per share (in dollars per share)	$ 0.78	$ 0.75	$ 0.72
Comprehensive income:
Net income	$ 47,141	$ 42,688	$ 36,430
Unrealized swap derivative gain arising during the period	1,648	3,665	541
Reclassification adjustment for amortization of interest expense included in net income	57	1,920	2,473
Other comprehensive income	1,705	5,585	3,014
Comprehensive income	$ 48,846	$ 48,273	$ 39,444