LOANS AND ALLOWANCE FOR CREDIT LOSSES - Receivables Past Due (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	$ 6,008
Non-accrual	7,304	$ 8,178
Loans Past Due 90 Days or More and Still Accruing	0	1
Financing receivable	1,893,906	1,829,448
Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	10,703	6,603
30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	5,754	4,084
60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	3,566	1,045
90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,383	1,474
Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,883,203	1,822,845
Construction
Financing Receivable, Past Due [Line Items]
Financing receivable	124,942
Commercial mortgages, other
Financing Receivable, Past Due [Line Items]
Financing receivable	923,585
Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Financing receivable	85,283
Indirect consumer loans
Financing Receivable, Past Due [Line Items]
Financing receivable	210,532
Direct consumer loans
Financing Receivable, Past Due [Line Items]
Financing receivable	10,674
Commercial and Agricultural
Financing Receivable, Past Due [Line Items]
Financing receivable	253,806	252,293
Commercial Mortgages
Financing Receivable, Past Due [Line Items]
Financing receivable	1,048,527	996,913
Commercial Mortgages | Construction
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	0
Non-accrual	0	5
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	124,942	108,243
Commercial Mortgages | Construction | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	4,407	0
Commercial Mortgages | Construction | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,163	0
Commercial Mortgages | Construction | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,244	0
Commercial Mortgages | Construction | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Commercial Mortgages | Construction | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	120,535	108,243
Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	3,500
Non-accrual	3,534	3,928
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	923,585	888,670
Commercial Mortgages | Commercial mortgages, other | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	596	1,544
Commercial Mortgages | Commercial mortgages, other | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	340	1,058
Commercial Mortgages | Commercial mortgages, other | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Commercial Mortgages | Commercial mortgages, other | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	256	486
Commercial Mortgages | Commercial mortgages, other | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	922,989	887,126
Residential Mortgages
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	926
Non-accrual	926	986
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	285,084	285,672
Residential Mortgages | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,307	2,363
Residential Mortgages | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,463	1,360
Residential Mortgages | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	482	709
Residential Mortgages | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	362	294
Residential Mortgages | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	282,777	283,309
Consumer Loans
Financing Receivable, Past Due [Line Items]
Financing receivable	306,489	294,570
Consumer Loans | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	749
Non-accrual	749	760
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	85,283	81,401
Consumer Loans | Home equity lines and loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	554	756
Consumer Loans | Home equity lines and loans | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	9	193
Consumer Loans | Home equity lines and loans | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	121
Consumer Loans | Home equity lines and loans | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	545	442
Consumer Loans | Home equity lines and loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	84,729	80,645
Consumer Loans | Indirect consumer loans
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	527
Non-accrual	527	540
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	210,532	202,124
Consumer Loans | Indirect consumer loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,833	1,840
Consumer Loans | Indirect consumer loans | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,242	1,397
Consumer Loans | Indirect consumer loans | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	374	193
Consumer Loans | Indirect consumer loans | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	217	250
Consumer Loans | Indirect consumer loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	208,699	200,284
Consumer Loans | Direct consumer loans
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	3
Non-accrual	3	13
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	10,674	11,045
Consumer Loans | Direct consumer loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	25	22
Consumer Loans | Direct consumer loans | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	11	2
Consumer Loans | Direct consumer loans | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	11	19
Consumer Loans | Direct consumer loans | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	3	1
Consumer Loans | Direct consumer loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	10,649	11,023
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Financing receivable	253,501
Commercial and industrial | Commercial and Agricultural
Financing Receivable, Past Due [Line Items]
Non-accrual with no allowance for credit losses	303
Non-accrual	1,565	1,946
Loans Past Due 90 Days or More and Still Accruing	0	1
Financing receivable	253,501	252,044
Commercial and industrial | Commercial and Agricultural | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	981	78
Commercial and industrial | Commercial and Agricultural | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	526	74
Commercial and industrial | Commercial and Agricultural | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	455	3
Commercial and industrial | Commercial and Agricultural | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	1
Commercial and industrial | Commercial and Agricultural | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	252,520	251,966
Agricultural
Financing Receivable, Past Due [Line Items]
Financing receivable	305
Agricultural | Commercial and Agricultural
Financing Receivable, Past Due [Line Items]
Financing receivable	305	249
Agricultural | Commercial and Agricultural | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Agricultural | Commercial and Agricultural | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Agricultural | Commercial and Agricultural | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Agricultural | Commercial and Agricultural | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Agricultural | Commercial and Agricultural | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	$ 305	$ 249