Note 7 - 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, 2018	Dec. 31, 2017	Dec. 31, 2016
Revenues	$ 506.3	$ 516.0	$ 597.5
Operating expenses	(146.1)	(150.7)	(178.1)
Impairment charges	(20.7)	(12.9)	(38.6)
Depreciation and amortization	(122.5)	(116.1)	(138.1)
Gain on sale of operating properties	60.3	26.0	296.2
Interest expense	(80.1)	(81.9)	(117.3)
Other (expense)/income, net	(4.4)	(3.0)	20.1
Net income	$ 192.8	$ 177.4	$ 441.7