Capital of the Operating Partnership (Details Textual)		9 Months Ended
		Sep. 30, 2016 USD ($) $ / shares shares	Dec. 31, 2015 shares
Limited Partners' Capital Account [Line Items]
Limited Partnership (LP), ownership interest ( percentage)		90.20%
Remaining units (in shares)	[1]	120,966,073
Equity, redemption basis		1
Redemption price, threshold consecutive trading days (days)		10 days
Temporary equity transferred to permanent equity (in shares)		117,658
Equity redemption of OP Units, Total Units (in shares)		991,550
OP Unit redemption (in shares)		613,762
Equity redemption, cash (in shares)		377,788
OP Units
Limited Partners' Capital Account [Line Items]
Redemption value (usd per share) | $ / shares		$ 22.08
Non-controlling interest redemption value | $		$ 260,800,000.0
Bellevue Marketplace [Member] | OP Units Classified as Mezzanine Equity
Limited Partners' Capital Account [Line Items]
Temporary equity, shares issued (shares)			1,946,483
Redeemable OP unit redemption (shares) | $		$ 1,828,825
Sternco Shopping Center | OP Units Classified as Mezzanine Equity
Limited Partners' Capital Account [Line Items]
Redemption value (usd per share) | $ / shares		$ 17.30
Payments for redemption of redeemable OP units | $		$ 31,600,000.0
ROIC Capital | Retail Opportunity Investments Partnership L.P.
Limited Partners' Capital Account [Line Items]
Remaining units (in shares)	[1]	109,156,012	99,531,034
OP Unit redemption (in shares)	[1]	613,762
Limited Partner’s Capital | Retail Opportunity Investments Partnership L.P.
Limited Partners' Capital Account [Line Items]
Remaining units (in shares)	[2]	11,810,061.000	12,195,603
OP Unit redemption (in shares)	[2]	(613,762)

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

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