Note 8 - Investment and Advances in Real Estate Joint Ventures - Investment and Advances to Real Estate Joint Ventures - Income Statements (Details) - Excluding KIR and Rio Can [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenues from rental properties	$ 597.5	$ 842.5	$ 1,059.9
Operating expenses	(178.1)	(265.9)	(333.5)
Interest expense	(117.3)	(202.8)	(247.3)
Depreciation and amortization	(138.1)	(191.9)	(260.0)
Impairment charges	(38.6)	(63.4)	(23.1)
Other income/(expense), net	20.1	4.4	(14.4)
	(452.0)	(719.6)	(878.3)
Income from continuing operations	145.5	122.9	181.6
Income from discontinued operations			2.8
Impairment on dispositions of properties			(3.8)
Gain on dispositions of properties			471.1
			470.1
Gain on sale of operating properties	296.2	1,166.7
Net income	$ 441.7	$ 1,289.6	$ 651.7