Consolidated statements of comprehensive income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statement of Comprehensive Income [Abstract]
Net tax (benefits) expenses on net change in unrealized gain (loss) on available-for-sale securities	$ (7,224)	$ 5,781	$ 6,227
Net tax expenses (benefits) on reclassification adjustment for gain on sale of securities included in net income	33	348	(24)
Net tax expenses (benefits) recognized on net change in unrealized gain (loss) on hedging activities	293	(363)	(322)
Net tax expenses on reclassification adjustment on gain on hedging activities	$ 0	$ 337	$ 170

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.

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=124509347&loc=d3e640-108580

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Amount of tax expense (benefit) for reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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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.

+ References

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-Topic 220
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
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