Note 5 - Other Real Estate Investments and Other Assets (Details Textual) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Maximum Exposure [Member] | Preferred Equity Investments [Member]
Equity Method Investments	$ 190,000		$ 190,000
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			$ 22,300	$ 16,500
Equity Method Investment, Realized Gain (Loss) on Disposal			$ 10,100	$ 9,200
Number of Capital Transactions	4	7	4	7
Equity Method Investments	$ 477,800		$ 477,800		$ 742,559
Number of Real Estate Properties	46	23	46	23
Income (Loss) from Equity Method Investments	$ 11,500	$ 10,900	$ 190,155	$ 130,808