Note 7 - Variable Interest Entities ("VIE") - Summary of Restricted Assets and VIE Liabilities (Details) $ in Thousands	Jun. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Number of consolidated VIEs	24	27
Restricted Assets:
Real estate, net	$ 102,600	$ 627,500
Cash and cash equivalents	3,500	9,800
Accounts and notes receivable, net	1,400	3,200
Other assets	2,500	4,500
Total Restricted Assets	109,987	644,990
VIE Liabilities:
Mortgages payable, net	35,300	340,900
Other liabilities	71,900	76,800
Total VIE Liabilities	$ 107,215	$ 417,688
Variable Interest Entity, Unencumbered [Member]
Number of consolidated VIEs	21	22
Variable Interest Entity, Encumbered by Third Party Non-resource Mortgage Debt [Member]
Number of consolidated VIEs	3	5