Note 4 - Investments and Advances in Real Estate Joint Ventures - The Company's Share of Net Income/(Loss) (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Kim Pru and Kim Pru II [Member]
Income (Loss) from Equity Method Investments	[1],[2]	$ 3,100	$ 2,400	$ 5,300	$ 3,600
KIR [Member]
Income (Loss) from Equity Method Investments	[1]	12,100	15,600	19,500	23,100
CPP [Member]
Income (Loss) from Equity Method Investments		900	2,400	4,800	4,900
Other Institutional Programs [Member]
Income (Loss) from Equity Method Investments		300	200	600	1,200
Other Joint Venture Programs [Member]
Income (Loss) from Equity Method Investments	[1],[3],[4],[5]	1,400	(6,100)	4,300	16,700
Canadian Properties [Member]
Income (Loss) from Equity Method Investments	[1]	90,900	7,900	144,100	70,400
Income (Loss) from Equity Method Investments		$ 108,700	$ 22,400	$ 178,618	$ 119,914

[1] Amounts include gains on sale of real estate properties, see table below.

[2] During the six months ended June 30, 2015, KimPru recognized impairment charges related to the pending disposition of four operating properties, of which the Company's share of these impairment charges was $1.1 million.

[3] During 2013, the Intown portfolio was sold and the Company maintained its guarantee on a portion of debt that was assumed by the buyer at closing. The transaction resulted in a deferred gain to the Company of $21.7 million due to the Company's continued involvement through its guarantee of the debt. On February 24, 2015, the outstanding debt balance was fully repaid by the buyer and as such, the Company was relieved of its related commitments and guarantee. As a result, the Company recognized the deferred gain of $21.7 million during the six months ended June 30, 2015.

[4] During the six months ended June 30, 2015, a joint venture in which the Company holds a noncontrolling interest recognized aggregate impairment charges of $2.6 million relating to the pending sale of various land parcels. The Company's share of these impairment charges was $1.3 million.

[5] During the six months ended June 30, 2015, a joint venture in which the Company holds a noncontrolling interest recognized an impairment charge relating to the pending sale of a property. The Company's share of this impairment charge was $4.1 million, before income tax benefit.