Note 6 - Other Comprehensive Income (Loss) - Components of Other Comprehensive (Loss) Income and Related Tax Effects (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Unrealized gains (losses) arising during the period	$ 106	$ (7,936)	$ 2,952	$ (21,682)
Unrealized gains (losses) arising during the period, tax	(599)	(1,685)	1	(5,413)
Unrealized gains (losses) arising during the period, net of tax	705	(6,251)	2,951	(16,269)
Other comprehensive income (loss)	106	(7,936)	2,952	(21,682)
Other comprehensive income (loss), tax	(599)	(1,685)	1	(5,413)
Other comprehensive income (loss), net of tax	$ 705	$ (6,251)	$ 2,951	$ (16,269)

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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