GOODWILL, CORE DEPOSIT INTANGIBLES AND OTHER INTANGIBLE ASSETS (Narrative) (Details)	12 Months Ended
Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Goodwill [Line Items]
Goodwill	$ 576,005,000	$ 576,005,000
Goodwill, impairment loss	0
Mortgage loans serviced for others	725,900,000	723,300,000
Custodial escrow balances maintained	5,100,000	4,500,000
Servicing rights, net	7,840,000	6,890,000
Mortgage Servicing Rights
Goodwill [Line Items]
Fair value of mortgage servicing rights	$ 7,840,000	$ 6,412,000
Prepayment rate (as a percent)	7.90%	13.40%
Discount rate	10.02%	9.02%
Fees collected for servicing of mortgage loans	$ 1,800,000	$ 1,800,000	$ 1,700,000
Servicing asset	$ 7,840,000	$ 6,412,000	5,189,000
Mortgage Servicing Rights \| Minimum \| Measurement Input, Cap Rate
Goodwill [Line Items]
Average capitalization rate (percent)	0.0083	0.0076
Mortgage Servicing Rights \| Maximum \| Measurement Input, Cap Rate
Goodwill [Line Items]
Average capitalization rate (percent)	0.0148	0.0120
Commercial Servicing Rights
Goodwill [Line Items]
Fair value of mortgage servicing rights	$ 0	$ 782,000
Fees collected for servicing of mortgage loans		536,000	879,000
Servicing rights, net	0	45,400,000
Servicing asset	$ 0	$ 478,000	$ 863,000
Commercial Servicing Rights \| Minimum
Goodwill [Line Items]
Prepayment rate (as a percent)		12.52%
Discount rate		9.20%
Commercial Servicing Rights \| Maximum
Goodwill [Line Items]
Prepayment rate (as a percent)		16.88%
Discount rate		10.66%
Commercial Servicing Rights less than 20 Years
Goodwill [Line Items]
Fair value of mortgage servicing rights		$ 98,000
Servicing rights, term	20 years	20 years
Servicing asset		$ 45,000
Commercial Servicing Rights more than 20 Years
Goodwill [Line Items]
Fair value of mortgage servicing rights		$ 684,000
Servicing rights, term	20 years	20 years
Servicing asset		$ 433,000

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Servicing Asset, Agreement Term

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No definition available.

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The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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Income from mortgage banking activities (fees and commissions) and servicing real estate mortgages, credit cards, and other financial assets held by others net of any related impairment of capitalized service costs. Also includes any premiums received in lieu of regular servicing fees on such loans only as earned over the life of the loans.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1402
-Subsection Instruction 3

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

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Amortized amount of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Fair value of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

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Value of input used to measure servicing asset.

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Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

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Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

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