Note 6 - Other Comprehensive Income (Loss) - Components of Other Comprehensive (Loss) Income and Related Tax Effects (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Unrealized gains (losses) arising during the period	$ 2,845	$ (13,746)
Unrealized gains (losses) arising during the period, tax	599	(3,728)
Unrealized gains (losses) arising during the period, net of tax	2,246	(10,018)
Other comprehensive income (loss)	2,845	(13,746)
Other comprehensive income (loss), tax	599	(3,728)
Other comprehensive income (loss), net of tax	$ 2,246	$ (10,018)

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

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

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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