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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Receivables Past Due (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Financing Receivable, Past Due [Line Items]
Nonaccrual with No Allowance for Credit Losses	$ 7,892	$ 8,529
Nonaccrual	10,545	10,411
Loans Past Due 90 Days or More and Still Accruing	0	10
Financing receivable	2,028,954	1,972,664
Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	12,691	14,360
30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	4,692	9,562
60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,231	943
90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	5,768	3,855
Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,016,263	1,958,304
Commercial and industrial
Financing Receivable, Past Due [Line Items]
Nonaccrual with No Allowance for Credit Losses	72	76
Nonaccrual	1,757	1,930
Loans Past Due 90 Days or More and Still Accruing	0	10
Financing receivable	289,266	264,396
Commercial and industrial | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,249	1,237
Commercial and industrial | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	144	1,196
Commercial and industrial | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	232	31
Commercial and industrial | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	873	10
Commercial and industrial | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	288,017	263,159
Commercial Mortgages
Financing Receivable, Past Due [Line Items]
Financing receivable	1,174,939	1,122,925
Commercial Mortgages | Construction Loans
Financing Receivable, Past Due [Line Items]
Nonaccrual with No Allowance for Credit Losses	1,432	2,209
Nonaccrual	1,432	2,209
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	138,710	138,887
Commercial Mortgages | Construction Loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,432	4,371
Commercial Mortgages | Construction Loans | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	2,164
Commercial Mortgages | Construction Loans | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Commercial Mortgages | Construction Loans | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,432	2,207
Commercial Mortgages | Construction Loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	137,278	134,516
Commercial Mortgages | Commercial mortgages, other
Financing Receivable, Past Due [Line Items]
Nonaccrual with No Allowance for Credit Losses	3,925	3,732
Nonaccrual	4,893	3,760
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	1,036,229	984,038
Commercial Mortgages | Commercial mortgages, other | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	3,150	1,386
Commercial Mortgages | Commercial mortgages, other | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	1,022
Commercial Mortgages | Commercial mortgages, other | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,014	103
Commercial Mortgages | Commercial mortgages, other | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,136	261
Commercial Mortgages | Commercial mortgages, other | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,033,079	982,652
Residential Mortgages
Financing Receivable, Past Due [Line Items]
Nonaccrual with No Allowance for Credit Losses	1,387	1,315
Nonaccrual	1,387	1,315
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	274,099	277,992
Residential Mortgages | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	3,408	3,030
Residential Mortgages | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,293	2,244
Residential Mortgages | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	341	201
Residential Mortgages | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	774	585
Residential Mortgages | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	270,691	274,962
Consumer Loans
Financing Receivable, Past Due [Line Items]
Financing receivable	290,650	307,351
Consumer Loans | Home equity lines and loans
Financing Receivable, Past Due [Line Items]
Nonaccrual with No Allowance for Credit Losses	517	508
Nonaccrual	517	508
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	92,449	87,056
Consumer Loans | Home equity lines and loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	852	914
Consumer Loans | Home equity lines and loans | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	437	461
Consumer Loans | Home equity lines and loans | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	192	87
Consumer Loans | Home equity lines and loans | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	223	366
Consumer Loans | Home equity lines and loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	91,597	86,142
Consumer Loans | Indirect consumer loans
Financing Receivable, Past Due [Line Items]
Nonaccrual with No Allowance for Credit Losses	559	687
Nonaccrual	559	687
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	189,504	210,423
Consumer Loans | Indirect consumer loans | Total Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	2,575	3,400
Consumer Loans | Indirect consumer loans | 30 - 59 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	1,806	2,473
Consumer Loans | Indirect consumer loans | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	439	501
Consumer Loans | Indirect consumer loans | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	330	426
Consumer Loans | Indirect consumer loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	186,929	207,023
Consumer Loans | Direct consumer loans
Financing Receivable, Past Due [Line Items]
Nonaccrual with No Allowance for Credit Losses	0	2
Nonaccrual	0	2
Loans Past Due 90 Days or More and Still Accruing	0	0
Financing receivable	8,697	9,872
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	12	2
Consumer Loans | Direct consumer loans | 60 - 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	13	20
Consumer Loans | Direct consumer loans | 90 Days or More Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	0	0
Consumer Loans | Direct consumer loans | Loans Not Past Due
Financing Receivable, Past Due [Line Items]
Financing receivable	$ 8,672	$ 9,850

X

- Definition

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

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