Note 12 - Supplemental Schedule of Non-cash Investing / Financing Activities - Non-Cash Investing and Financing Activities (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Acquisition of real estate interests by assumption of mortgage debt	$ 33,174	$ 20,800
Acquisition of real estate interests through proceeds held in escrow	66,044	39,849
Proceeds held in escrow through sale of real estate interests	66,431	36,733
Disposition of real estate interests by assignment of debt		15,744
Disposition of real estate interests through the issuance of mortgage receivable		5,730
Issuance of common stock	85	488
Surrender of restricted common stock	(6,904)	(5,604)
Declaration of dividends paid in succeeding period	118,136	111,480	$ 115,182
(Decrease)/increase in capital expenditures accrual	(5,582)	11,700
Increase in real estate and other assets	316,772	977,807
Increase in mortgages payable, other liabilities and non-controlling interests	$ 194,964	$ 694,530