Note 7 - Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%
Net Deferred Tax Assets (Liabilities)	$ 4,900		$ 6,300
Deferred Tax Assets, Operating Loss Carryforwards, Total	3,900
Operating Loss Carryforwards, Total	20,000
Deferred Tax Assets, Valuation Allowance, Total	$ 0		$ 0