Note 7 - Variable Interest Entities ("VIE") - Summary of Restricted Assets and VIE Liabilities (Details) $ in Thousands	Sep. 30, 2018 USD ($)	Dec. 31, 2017 USD ($)
Number of consolidated VIEs	24	27
Restricted Assets:
Real estate, net	$ 101,600	$ 627,500
Real estate under development	120,900
Cash and cash equivalents	3,500	9,800
Accounts and notes receivable, net	4,800	3,200
Other assets	3,400	4,500
Total Restricted Assets	234,165	644,990
VIE Liabilities:
Mortgages and construction loan payable, net	63,600	340,900
Other liabilities	79,800	76,800
Total VIE Liabilities	$ 143,399	$ 417,688
Variable Interest Entity, Unencumbered [Member]
Number of consolidated VIEs	20	22
Variable Interest Entity, Encumbered by Third Party Non-resource Mortgage Debt [Member]
Number of consolidated VIEs	4	5