Note 3 - Other Comprehensive Loss - Components of Other Comprehensive (Loss) Income and Related Tax Effects (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Gross unrealized (losses) gains arising during the period, before tax	$ (24,098)	$ (3,979)
Gross unrealized (losses) gains arising during the period, tax	(5,920)	(1,114)
Gross unrealized (losses) gains arising during the period, net of tax	(18,178)	(2,865)
Other comprehensive income (loss), before tax	(24,098)	(3,979)
Other comprehensive income (loss), tax	(5,920)	(1,114)
Other comprehensive income (loss), net of tax	$ (18,178)	$ (2,865)

Amount before tax of other comprehensive income (loss) attributable to parent entity.

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