Note 10 - Income Taxes (Details Textual) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Effective Income Tax Rate Reconciliation, Federal Transition Tax Payable, Amount			$ (476)	$ 476
Reversal of Transition Tax Payable	$ 476
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount		$ 7	$ 129
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		21.00%	21.00%