Note 7 - Investment and Advances in Real Estate Joint Ventures (Details) - Investment and Advances to Real Estate Joint Ventures - Income Statements - Excluding KIR and RioCan [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Investments [Line Items]
Revenues from rental property	$ 842.5	$ 1,059.9	$ 1,280.2
Operating expenses	(265.9)	(333.5)	(410.3)
Interest expense	(202.8)	(247.3)	(316.4)
Depreciation and amortization	(191.9)	(260.0)	(298.8)
Impairment charges	(63.4)	(23.1)	(32.3)
Other income/(expense), net	4.4	(14.4)	(16.2)
	(719.6)	(878.3)	(1,074.0)
Income from continuing operations	122.9	181.6	206.2
Discontinued Operations:
Income from discontinued operations	0.0	2.8	14.1
Impairment on dispositions of properties	0.0	(3.8)	(14.8)
Gain on dispositions of properties	0.0	471.1	229.5
	0.0	470.1	228.8
Gain on sale of operating properties	1,166.7	0.0	0.0
Net income	$ 1,289.6	$ 651.7	$ 435.0