Note 4 - Other Revenues - Summary of Other Revenues (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Rental income	$ 5,532	$ 5,485
Management and accounting services fees	3,708	3,859
Insurance services	1,692	1,559
Other	337	381
Total other revenues	$ 11,269	$ 11,284