Note 5 - Other Real Estate Investments and Other Assets (Details Textual) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Maximum Exposure [Member] | Preferred Equity Investments [Member]
Equity Method Investments	$ 188,600		$ 188,600
Preferred Equity Investments [Member] | Leased Properties [Member]
Number of Real Estate Properties	350		350
Preferred Equity Investments [Member]
Number of Real Estate Properties	373		373
Income (Loss) from Equity Method Investments			$ 18,700	$ 10,900
Equity Method Investment, Realized Gain (Loss) on Disposal			$ 10,000	$ 1,000
Number of Capital Transactions	4	2	4	2
Equity Method Investments	$ 519,268		$ 519,268		$ 742,559
Income (Loss) from Equity Method Investments	$ 108,700	$ 22,400	$ 178,618	$ 119,914