LOANS AND ALLOWANCE FOR CREDIT LOSSES - Troubled Debt Restructurings (TDRs) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($) loan	Dec. 31, 2021 USD ($) loan	Dec. 31, 2020 USD ($) loan
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	194	232	247
TDRs, amount	$ 5,629	$ 8,239	$ 6,984
Number of loans modified in TDR	24	54	55
Loans modified in TDR during the year, amount	$ 784	$ 3,087	$ 1,756
Business lending loans	$ 500
Nonaccrual
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	62	81	73
TDRs, amount	$ 2,461	$ 3,940	$ 3,227
Accruing
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	132	151	174
TDRs, amount	$ 3,168	$ 4,299	$ 3,757
Commercial Portfolio Segment \| Business Lending
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	4	14	10
TDRs, amount	$ 406	$ 1,822	$ 720
Number of loans modified in TDR \| loan	0	5	1
Loans modified in TDR during the year, amount	$ 0	$ 1,371	$ 4
Commercial Portfolio Segment \| Business Lending \| Nonaccrual
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	1	10	6
TDRs, amount	$ 135	$ 1,011	$ 529
Commercial Portfolio Segment \| Business Lending \| Accruing
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	3	4	4
TDRs, amount	$ 271	$ 811	$ 191
Residential Portfolio Segment \| Consumer Mortgage
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	98	108	104
TDRs, amount	$ 4,332	$ 5,114	$ 4,679
Number of loans modified in TDR \| loan	7	24	17
Loans modified in TDR during the year, amount	$ 597	$ 1,425	$ 1,339
Residential Portfolio Segment \| Consumer Mortgage \| Nonaccrual
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	52	61	56
TDRs, amount	$ 2,218	$ 2,694	$ 2,413
Residential Portfolio Segment \| Consumer Mortgage \| Accruing
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	46	47	48
TDRs, amount	$ 2,114	$ 2,420	$ 2,266
Consumer Portfolio Segment \| Consumer Indirect
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	56	72	86
TDRs, amount	$ 600	$ 829	$ 951
Number of loans modified in TDR \| loan	13	23	31
Loans modified in TDR during the year, amount	$ 178	$ 284	$ 333
Consumer Portfolio Segment \| Consumer Indirect \| Nonaccrual
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	0	0	0
TDRs, amount	$ 0	$ 0	$ 0
Consumer Portfolio Segment \| Consumer Indirect \| Accruing
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	56	72	86
TDRs, amount	$ 600	$ 829	$ 951
Consumer Portfolio Segment \| Consumer Direct
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	18	16	23
TDRs, amount	$ 5	$ 7	$ 85
Number of loans modified in TDR \| loan	3	2	3
Loans modified in TDR during the year, amount	$ 5	$ 7	$ 10
Consumer Portfolio Segment \| Consumer Direct \| Nonaccrual
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	0	0	0
TDRs, amount	$ 0	$ 0	$ 0
Consumer Portfolio Segment \| Consumer Direct \| Accruing
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	18	16	23
TDRs, amount	$ 5	$ 7	$ 85
Consumer Portfolio Segment \| Home Equity
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	18	22	24
TDRs, amount	$ 286	$ 467	$ 549
Number of loans modified in TDR \| loan	1	0	3
Loans modified in TDR during the year, amount	$ 4	$ 0	$ 70
Consumer Portfolio Segment \| Home Equity \| Nonaccrual
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	9	10	11
TDRs, amount	$ 108	$ 235	$ 285
Consumer Portfolio Segment \| Home Equity \| Accruing
Troubled Debt Restructurings (TDRs)
TDRs, number \| loan	9	12	13
TDRs, amount	$ 178	$ 232	$ 264

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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