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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Receivables Past Due (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	$ 8,529	$ 7,198
Non-accrual	10,411	8,178
Loans Past Due 90 Days or More and Still Accruing	10	1
Financing receivable	1,972,664	1,829,448
Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	14,360	6,603
30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	9,562	4,084
60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	943	1,045
90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	3,855	1,474
Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,958,304	1,822,845
Construction
Financing Receivable, Past Due [Line Items]
Financing receivable	138,887
Commercial mortgages
Financing Receivable, Past Due [Line Items]
Financing receivable	984,038
Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Financing receivable	87,056
Indirect consumer loans
Financing Receivable, Past Due [Line Items]
Financing receivable	210,423
Direct consumer loans
Financing Receivable, Past Due [Line Items]
Financing receivable	9,872
Commercial Mortgages
Financing Receivable, Past Due [Line Items]
Financing receivable	1,122,925	996,913
Commercial Mortgages | Construction
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	2,209	5
Non-accrual	2,209	5
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	138,887	108,243
Commercial Mortgages | Construction | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	4,371	0
Commercial Mortgages | Construction | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,164	0
Commercial Mortgages | Construction | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Commercial Mortgages | Construction | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,207	0
Commercial Mortgages | Construction | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	134,516	108,243
Commercial Mortgages | Commercial mortgages
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	3,732	3,890
Non-accrual	3,760	3,928
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	984,038	888,670
Commercial Mortgages | Commercial mortgages | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,386	1,544
Commercial Mortgages | Commercial mortgages | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,022	1,058
Commercial Mortgages | Commercial mortgages | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	103	0
Commercial Mortgages | Commercial mortgages | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	261	486
Commercial Mortgages | Commercial mortgages | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	982,652	887,126
Residential Mortgages
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	1,315	986
Non-accrual	1,315	986
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	277,992	285,672
Residential Mortgages | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	3,030	2,363
Residential Mortgages | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,244	1,360
Residential Mortgages | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	201	709
Residential Mortgages | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	585	294
Residential Mortgages | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	274,962	283,309
Consumer Loans
Financing Receivable, Past Due [Line Items]
Financing receivable	307,351	294,570
Consumer Loans | Credit cards
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	0	0
Non-accrual	0	0
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	0	0
Consumer Loans | Credit cards | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Consumer Loans | Credit cards | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Consumer Loans | Credit cards | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Consumer Loans | Credit cards | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Consumer Loans | Credit cards | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Consumer Loans | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	508	729
Non-accrual	508	760
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	87,056	81,401
Consumer Loans | Home equity lines and loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	914	756
Consumer Loans | Home equity lines and loans | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	461	193
Consumer Loans | Home equity lines and loans | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	87	121
Consumer Loans | Home equity lines and loans | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	366	442
Consumer Loans | Home equity lines and loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	86,142	80,645
Consumer Loans | Indirect consumer loans
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	687	540
Non-accrual	687	540
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	210,423	202,124
Consumer Loans | Indirect consumer loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	3,400	1,840
Consumer Loans | Indirect consumer loans | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,473	1,397
Consumer Loans | Indirect consumer loans | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	501	193
Consumer Loans | Indirect consumer loans | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	426	250
Consumer Loans | Indirect consumer loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	207,023	200,284
Consumer Loans | Direct consumer loans
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	2	13
Non-accrual	2	13
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	9,872	11,045
Consumer Loans | Direct consumer loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	22	22
Consumer Loans | Direct consumer loans | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2	2
Consumer Loans | Direct consumer loans | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	20	19
Consumer Loans | Direct consumer loans | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	1
Consumer Loans | Direct consumer loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	9,850	11,023
Commercial and Agricultural Sector | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	76	1,035
Non-accrual	1,904	1,946
Loans Past Due 90 Days or More and Still Accruing	10	1
Financing receivable	264,140	252,044
Commercial and Agricultural Sector | Commercial and industrial | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,237	78
Commercial and Agricultural Sector | Commercial and industrial | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,196	74
Commercial and Agricultural Sector | Commercial and industrial | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	31	3
Commercial and Agricultural Sector | Commercial and industrial | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	10	1
Commercial and Agricultural Sector | Commercial and industrial | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	262,903	251,966
Commercial and Agricultural Sector | Agricultural
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	0	0
Non-accrual	26	0
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	256	249
Commercial and Agricultural Sector | Agricultural | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Commercial and Agricultural Sector | Agricultural | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Commercial and Agricultural Sector | Agricultural | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Commercial and Agricultural Sector | Agricultural | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Commercial and Agricultural Sector | Agricultural | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	$ 256	$ 249

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