Consolidated Statements of Comprehensive Income (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Amortization of prior service credits, tax	$ 26	$ 12	$ 12
Amortization of net actuarial losses, tax	(40)	(167)	(249)
Unrecognized actuarial gains (losses), tax	(290)	(1,162)	(146)
Change in net unrealized (losses) gains on securities available for sale, tax	(5,211)	4,473	1,783
Reclassification adjustment for net losses included in net income, tax	(5)	(595)	(78)
Net unrealized (loss) gain on cash flow hedge, tax	4,353	(1,538)	$ (179)
Change in fair value of liabilities related to instrument-specific credit risk, tax	$ (74)	$ (35)

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, before reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e640-108580

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Amount, after reclassification adjustment, of tax expense (benefit) of gain (loss) from increase (decrease) in instrument-specific credit risk of financial liability measured under fair value option.

+ References

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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) of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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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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