Capital of the Operating Partnership (Details Textual)	6 Months Ended
	Jun. 30, 2016 USD ($) $ / shares shares	Dec. 31, 2015 shares
Limited Partners' Capital Account [Line Items]
Limited Partners' Capital Account, units outstanding (shares)	114,159,167
Limited Partnership (LP), ownership interest ( percentage)	89.30%
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)	621,914
OP Unit redemption (in shares)	244,126
Equity redemption, cash (in shares)	377,788
OP Units
Limited Partners' Capital Account [Line Items]
Redemption value (usd per share) | $ / shares	$ 20.82
Non-controlling interest redemption value | $	$ 253,600,000.0
Sternco Shopping Center | 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
Redemption value (usd per share) | $ / shares	$ 17.30
Payments for redemption of redeemable OP units | $	$ 31,600,000.0
ROCI Capital | Retail Opportunity Investments Partnership L.P.
Limited Partners' Capital Account [Line Items]
Limited Partners' Capital Account, units outstanding (shares)	101,979,470