Note 8 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	35.00%
Operating Loss Carryforwards that Do Not Expire	$ 2,600
Elimination of AMT Operating Loss Carryforwards	91,300
Income Tax Expense (Benefit), Total	$ (4,999)
Percentage of AMT Credit Carryforward to Be Received	50.00%
Amount of AMT Credit Carryforwards Expected to Be Received	$ 2,500
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	12,100
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total	71,700
State and Local Jurisdiction [Member]
Operating Loss Carryforwards, Total	$ 85,700