Consolidated Statement of Partners' Capital (Unaudited) - 9 months ended Sep. 30, 2015 - USD ($) $ in Thousands		Retail Opportunity Investments Partnership L.P. [Member] Limited Partner’s Capital [Member]	[1]	Retail Opportunity Investments Partnership L.P. [Member] ROIC Capital [Member] Officer [Member]	[2]	Retail Opportunity Investments Partnership L.P. [Member] ROIC Capital [Member]		Retail Opportunity Investments Partnership L.P. [Member] AOCI Attributable to Parent [Member]	Retail Opportunity Investments Partnership L.P. [Member] Officer [Member]	Retail Opportunity Investments Partnership L.P. [Member]	AOCI Attributable to Parent [Member]	Officer [Member]	Total
Balance at Dec. 31, 2014		$ 39,070				$ 932,594	[2]	$ (8,882)		$ 962,782
Balance (in Shares) at Dec. 31, 2014		3,921,314				92,991,333	[2]
OP Units issued under the 2009 Plan (in Shares)	[2]					360,627
Repurchase of OP Units						$ (1,316)	[2]			(1,316)			$ (1,316)
Repurchase of OP Units (in Shares)	[2]					(78,570)
Cancellation of OP Units (in Shares)	[2]					(2,832)
Stock based compensation expense						$ 3,490	[2]			3,490			3,490
Adjustment to non-controlling interests ownership in Operating Partnership		$ 2,702				(2,702)	[2]
Issuance of OP Units in connection with sale of common stock						$ 101,293	[2]			101,293			(101,293)
Issuance of OP Units in connection with sale of common stock (in Shares)	[2]					6,064,567
Redemption of OP Units		$ (2,731)				$ 2,731	[2]
Redemption of OP Units (in Shares)		(150,000)				150,000	[2]
Registration expenditures						$ (4,247)	[2]			(4,247)			(4,247)
Cash distributions ($0.51 per unit)		$ (1,950)				(48,797)	[2]			(50,747)
Dividends payable to officers				$ (121)					$ (121)			$ (121)	(50,747)
Net income attributable to Retail Opportunity Investments Partnership, LP		681				16,943	[2]			17,624			17,624
Other comprehensive income								1,604		1,604	$ 1,604		$ 1,604
Balance at Sep. 30, 2015		$ 37,772				$ 999,868	[2]	$ (7,278)		$ 1,030,362
Balance (in Shares) at Sep. 30, 2015		3,771,314				99,485,125	[2]

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

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