Note 5 - Income Taxes - Reconciliation of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Balance at January 1	$ 42	$ 13
Additions based on tax positions related to the current year	4	29
Additions for tax positions of prior years	0	0
Reductions for tax positions of prior years	0	0
Settlements	0	0
Removal for tax provisions of prior years	0	0
Balance at December 31	$ 46	$ 42

Amount of unrecognized tax benefits.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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