Note 4 - Investments (Details Textual) $ in Thousands	3 Months Ended
Mar. 31, 2023 USD ($)
Other than Temporary Impairment Loss, Investments, Portion in Other Comprehensive Loss, Net of Tax, Attributable to Parent, Held-to-Maturity Securities	$ 0

Amount after tax of amount of other than temporary impairment (OTTI) on investment in held-to-maturity debt security, recognized in other comprehensive loss, attributable to parent entity.

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-Topic 220
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