Note 3 - Income Taxes - Valuation Allowances (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Balance at January 1	$ 15,627	$ 14,950
Charged to costs and expenses	72	677
(Deductions)/Other	0	0
Balance at December 31	$ 15,699	$ 15,627

Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-2

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