Note 6 - Other Comprehensive Income (Loss) - Components of Other Comprehensive (Loss) Income and Related Tax Effects (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Gross unrealized (losses) gains arising during the period, before tax	$ (957)	$ (281)	$ (2,092)	$ 1,800
Gross unrealized (losses) gains arising during the period, tax	(269)	(79)	(584)	503
Gross unrealized (losses) gains arising during the period, net of tax	(688)	(202)	(1,508)	1,297
Other comprehensive income (loss), before tax	(957)	(281)	(2,092)	1,800
Other comprehensive income (loss), tax	(269)	(79)	(584)	503
Other comprehensive income (loss), net of tax	$ (688)	$ (202)	$ (1,508)	$ 1,297

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

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