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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Receivables Past Due (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Past Due [Line Items]
Nonaccrual with no allowance for credit losses	$ 6,518	$ 8,529
Nonaccrual	8,954	10,411
Loans Past Due 90 Days or More and Still Accruing	23	10
Financing receivable	2,071,419	1,972,664
Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	11,891	14,360
30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	5,047	9,562
60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,588	943
Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	5,256	3,855
Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,059,528	1,958,304
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Nonaccrual with no allowance for credit losses	76	76
Nonaccrual	1,534	1,930
Loans Past Due 90 Days or More and Still Accruing	23	10
Financing receivable	299,521	264,396
Commercial and industrial | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,043	1,237
Commercial and industrial | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	140	1,196
Commercial and industrial | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	201	31
Commercial and industrial | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	702	10
Commercial and industrial | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	298,478	263,159
Commercial Mortgages
Financing Receivable, Past Due [Line Items]
Financing receivable	1,217,004	1,122,925
Commercial Mortgages | Construction
Financing Receivable, Past Due [Line Items]
Nonaccrual with no allowance for credit losses	0	2,209
Nonaccrual	0	2,209
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	94,943	138,887
Commercial Mortgages | Construction | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	4,371
Commercial Mortgages | Construction | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	2,164
Commercial Mortgages | Construction | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Commercial Mortgages | Construction | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	2,207
Commercial Mortgages | Construction | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	94,943	134,516
Commercial Mortgages | Commercial mortgages
Financing Receivable, Past Due [Line Items]
Nonaccrual with no allowance for credit losses	3,981	3,732
Nonaccrual	4,959	3,760
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	1,122,061	984,038
Commercial Mortgages | Commercial mortgages | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	4,290	1,386
Commercial Mortgages | Commercial mortgages | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,032	1,022
Commercial Mortgages | Commercial mortgages | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	103
Commercial Mortgages | Commercial mortgages | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	3,258	261
Commercial Mortgages | Commercial mortgages | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,117,771	982,652
Residential Mortgages
Financing Receivable, Past Due [Line Items]
Nonaccrual with no allowance for credit losses	1,372	1,315
Nonaccrual	1,372	1,315
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	274,979	277,992
Residential Mortgages | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,887	3,030
Residential Mortgages | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,529	2,244
Residential Mortgages | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	662	201
Residential Mortgages | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	696	585
Residential Mortgages | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	272,092	274,962
Consumer loans:
Financing Receivable, Past Due [Line Items]
Financing receivable	279,915	307,351
Consumer loans: | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Nonaccrual with no allowance for credit losses	613	508
Nonaccrual	613	508
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	93,220	87,056
Consumer loans: | Home equity lines and loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	595	914
Consumer loans: | Home equity lines and loans | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	231	461
Consumer loans: | Home equity lines and loans | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	87
Consumer loans: | Home equity lines and loans | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	364	366
Consumer loans: | Home equity lines and loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	92,625	86,142
Consumer loans: | Indirect consumer loans
Financing Receivable, Past Due [Line Items]
Nonaccrual with no allowance for credit losses	474	687
Nonaccrual	474	687
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	178,118	210,423
Consumer loans: | Indirect consumer loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	3,055	3,400
Consumer loans: | Indirect consumer loans | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,101	2,473
Consumer loans: | Indirect consumer loans | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	719	501
Consumer loans: | Indirect consumer loans | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	235	426
Consumer loans: | Indirect consumer loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	175,063	207,023
Consumer loans: | Direct consumer loans
Financing Receivable, Past Due [Line Items]
Nonaccrual with no allowance for credit losses	2	2
Nonaccrual	2	2
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	8,577	9,872
Consumer loans: | Direct consumer loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	21	22
Consumer loans: | Direct consumer loans | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	14	2
Consumer loans: | Direct consumer loans | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	6	20
Consumer loans: | Direct consumer loans | Greater Than 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1	0
Consumer loans: | Direct consumer loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	$ 8,556	$ 9,850

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