Consolidated Statements of Comprehensive Income (Parentheticals) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Amortization of actuarial losses, taxes	$ 39	$ 30	$ 116	$ 91
Amortization of prior service credits, taxes	(7)	(6)	(19)	(20)
Net unrealized gains (losses) on securities, taxes	(1,209)	1,449	(1,518)	2,000
Reclassification adjustment for net losses included in net income, taxes	3		(35)	29
Net unrealized gains (losses) on cash flow hedges, taxes	910	849	4,485	(6,253)
Change in fair value of liabilities related to instrument-specific credit risk, taxes	$ 27	$ 50	$ 139	$ 280

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=121641772&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, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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