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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Loan Portfolio (Details) - USD ($) $ in Thousands	Dec. 31, 2023		Dec. 31, 2022		Dec. 31, 2021
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	$ 1,972,664		$ 1,829,448
Allowance for credit losses	(22,517)	[1]	(19,659)	[1]	$ (21,025)
Loans, net	1,950,147		1,809,789
Construction
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	138,887
Home equity lines and loans
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	87,056
Indirect consumer loans
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	210,423
Direct consumer loans
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	9,872
Commercial and Agricultural
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	264,396		252,293
Allowance for credit losses	(5,055)		(3,373)		(3,591)
Commercial Mortgages
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	1,122,925		996,913
Allowance for credit losses	(12,026)		(11,576)		(13,556)
Commercial Mortgages | Construction
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	138,887		108,243
Commercial Mortgages | Commercial mortgages, other
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	984,038		888,670
Residential Mortgages
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	277,992		285,672
Allowance for credit losses	(2,194)		(1,845)		(1,803)
Consumer Loans
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	307,351		294,570
Allowance for credit losses	(3,242)		(2,865)		$ (2,075)
Consumer Loans | Home equity lines and loans
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	87,056		81,401
Consumer Loans | Indirect consumer loans
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	210,423		202,124
Consumer Loans | Direct consumer loans
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	9,872		11,045
Commercial and industrial
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	264,140
Commercial and industrial | Commercial and Agricultural
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	264,140		252,044
Allowance for credit losses	(900)
Agricultural
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	256
Agricultural | Commercial and Agricultural
Composition of loan portfolio [Abstract]
Total loans, net of deferred loan fees and costs	$ 256		$ 249
[1] Effective January 1, 2023, the allowance calculation is based upon Current Expected Credit loss methodology. Prior to January 1, 2023, the allowance calculation was based upon incurred loss methodology. Refer to Note 1 for further discussion.

X

- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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- Definition

Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
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-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

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-URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B

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