Consolidated Statements of Comprehensive Income (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Unrealized holding gain (loss) on available for sale securities, tax	$ 1,486	$ (595)	$ 296
Reclassification adjustment for gain included in net income, tax	(119)	(4)	(4)
Transfer from held to maturity to available for sale securities, tax		237
Net pension gain (losses) arising during the period, tax	(394)	(249)	115
Amortization of prior service cost included in net periodic pension cost, tax	(23)	(24)	(38)
Other comprehensive income (loss), tax	$ 950	$ (635)	$ 369

Amount of tax expense (benefit) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) related to transfers of securities into the available-for-sale category and out of the held-to-maturity category.

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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