Note 8 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%
Effective Income Tax Rate Reconciliation, Percent, Total	1.00%	30.00%
Deferred Tax Assets, Valuation Allowance, Total	$ 4,651	$ 1,275
Deferred Tax Assets, Operating Loss Carryforwards, Domestic	125,000
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	158,000
State and Local Jurisdiction [Member]
Deferred Tax Assets, Valuation Allowance, Total	4,700	$ 1,300
Domestic Tax Authority [Member] | Pre-2018 [Member]
Operating Loss Carryforwards, Total	56,000
Domestic Tax Authority [Member] | Post 2017 [Member]
Operating Loss Carryforwards, Total	$ 69,000