Note 8 - Capital of the Operating Partnership (Details) - USD ($) $ / shares in Units, $ in Millions		9 Months Ended
	Apr. 03, 2015	Sep. 30, 2015	Dec. 31, 2014
Note 8 - Capital of the Operating Partnership (Details) [Line Items]
Limited Partners' Capital Account, Units Outstanding		103,256,439
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest		96.30%
Common Stock, Shares, Outstanding		99,485,125	92,991,333
Minority Interest Decrease From Redemptions, Number of Units	150,000
ROIC common stock	150,000
OP Units [Member]
Note 8 - Capital of the Operating Partnership (Details) [Line Items]
Partners' Capital Account, Units		3,771,314
Non Controlling Interest Redemption Value (in Dollars)		$ 63.0
Non Controlling Interests Redemption Value Price Per Share (in Dollars per share)		$ 16.71