Note 2 - Summary of Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Operating Lease, Right-of-Use Asset			$ 98,210		$ 0
Operating Lease, Liability, Total			91,621
Accounting Standards Update 2016-02 [Member]
Operating Lease, Right-of-Use Asset			106,000	$ 106,000
Intangible Assets, Net (Excluding Goodwill), Total			7,300
Operating Lease, Liability, Total			$ 98,700	$ 98,700
Reclassification of Reimbursement Income From Revenues From Rental Properties [Member]
Prior Period Reclassification Adjustment	$ 58,000	$ 182,900
Other Rental Property [Member]
Prior Period Reclassification Adjustment	$ 5,600	$ 16,800