Consolidated Statement of Partners' Capital - 6 months ended Jun. 30, 2018 - USD ($) $ in Thousands		Total	Officer	Retail Opportunity Investments Partnership L.P.	Retail Opportunity Investments Partnership L.P. Officer	Retail Opportunity Investments Partnership L.P. Limited Partner’s Capital		Retail Opportunity Investments Partnership L.P. ROIC Capital		Retail Opportunity Investments Partnership L.P. ROIC Capital Officer	[2]	Retail Opportunity Investments Partnership L.P. Accumulated other comprehensive income
Balance (in shares) at Dec. 31, 2017						11,678,991	[1]	112,347,451	[2]
Balance at Dec. 31, 2017				$ 1,329,641		$ 125,674	[1]	$ 1,202,111	[2]			$ 1,856
Increase (Decrease) in Partners' Capital [Roll Forward]
OP units issued under the Equity Incentive Plan (in shares)	[2]							373,861
OP Units withheld for employee taxes (in shares)	[2]							(70,168)
OP Units withheld for employee taxes		$ (1,400)		(1,400)				$ (1,400)	[2]
Cancellation of OP Units (in shares)	[2]							(6,999)
Cancellation of OP Units				0				$ 0	[2]
Stock based compensation expense		3,419		3,419				3,419	[2]
Cash redemption of OP Units (in units)						(30,889)
Cash redemption of OP Units		560		(560)		$ (560)
Adjustment to non-controlling interests ownership in Operating Partnership						713	[1]	$ (713)	[2]
Issuance of OP Units in connection with sale of common stock (in shares)	[2]							75,314
Issuance of OP Units in connection with sale of common stock		1,508		1,508				$ 1,508	[2]
Registration expenditures		(118)		(118)				(118)	[2]
Cash distributions ($0.39 per unit)				(48,514)		(4,553)	[1]	(43,961)	[2]
Dividends payable to officers		(48,514)	$ (160)		$ (160)					$ (160)
Net income attributable to Retail Opportunity Investments Partnership, LP		19,926		19,926		$ 1,885	[1]	$ 18,041	[2]
Other comprehensive income		$ 5,379		5,379								5,379
Balance (in shares) at Jun. 30, 2018		124,367,561				11,648,102	[1]	112,719,459	[2]
Balance at Jun. 30, 2018				$ 1,309,121		$ 123,159	[1]	$ 1,178,727	[2]			$ 7,235

[1] Consists of limited partnership interests held by third parties.

[2] Consists of general and limited partnership interests held by ROIC.