Note 9 - Notes Payable and Special Assessment Obligations - Debt, Notes Payable, and Special Assessment Obligations (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Long-term debt, gross	$ 35,538	$ 34,551
Less: deferred financing costs of notes payable	(365)	(446)
Total notes payable, net	35,173	34,105
Secured Debt [Member] | The $32.3 Million Notes Payable [Member]
Long-term debt, gross	20,098	19,557
Secured Debt [Member] | The $5.9 Million Notes Payable [Member]
Long-term debt, gross	5,940	5,940
Secured Debt [Member] | Special Assessment Bonds [Member]
Long-term debt, gross	103	116
Unsecured Debt [Member] | The $10.2 Million Notes Payable [Member]
Long-term debt, gross	$ 9,397	$ 8,938