ALLOWANCE FOR CREDIT LOSSES - LOANS - Residential and consumer portfolio (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Performing and non-performing outstanding balances of the residential and consumer portfolios
Total loans	$ 1,067,949	$ 1,038,271
Current period gross charge-offs, Total	2,205	3,641
Residential mortgages
Performing and non-performing outstanding balances of the residential and consumer portfolios
Total loans	177,110	174,670
Current period gross charge-offs, Total	0	54
Residential and Consumer
Performing and non-performing outstanding balances of the residential and consumer portfolios
2024/2023	24,353	28,481
2023/2022	26,700	32,050
2022/2021	26,843	70,954
2021/2020	65,145	47,312
2020/2019	44,402	8,303
PRIOR	43,466	40,956
REVOLVING LOANS AMORTIZED COST BASIS	54,148	48,501
REVOLVING LOANS CONVERTED TO TERM	664	888
Total loans	285,721	277,445
Current period gross charge-offs, 2024/2023	5	9
Current period gross charge-offs, 2023/2022	6	35
Current period gross charge-offs, 2022/2021	21	43
Current period gross charge-offs, 2021/2020	19	7
Current period gross charge-offs, 2020/2019	13	8
Current period gross charge-offs, Prior	143	227
Current period gross charge-offs, Total	207	329
Residential and Consumer \| Residential mortgages
Performing and non-performing outstanding balances of the residential and consumer portfolios
2024/2023	12,877	14,576
2023/2022	15,602	11,620
2022/2021	10,400	61,172
2021/2020	57,540	44,049
2020/2019	41,868	7,092
PRIOR	38,823	36,161
Total loans	177,110	174,670
Current period gross charge-offs, Prior		54
Current period gross charge-offs, Total		54
Residential and Consumer \| Consumer
Performing and non-performing outstanding balances of the residential and consumer portfolios
2024/2023	11,476	13,905
2023/2022	11,098	20,430
2022/2021	16,443	9,782
2021/2020	7,605	3,263
2020/2019	2,534	1,211
PRIOR	4,643	4,795
REVOLVING LOANS AMORTIZED COST BASIS	54,148	48,501
REVOLVING LOANS CONVERTED TO TERM	664	888
Total loans	108,611	102,775
Current period gross charge-offs, 2024/2023	5	9
Current period gross charge-offs, 2023/2022	6	35
Current period gross charge-offs, 2022/2021	21	43
Current period gross charge-offs, 2021/2020	19	7
Current period gross charge-offs, 2020/2019	13	8
Current period gross charge-offs, Prior	143	173
Current period gross charge-offs, Total	207	275
Performing \| Residential and Consumer
Performing and non-performing outstanding balances of the residential and consumer portfolios
2024/2023	24,353	28,466
2023/2022	26,590	32,050
2022/2021	26,797	70,954
2021/2020	65,145	47,239
2020/2019	44,343	8,261
PRIOR	42,717	39,958
REVOLVING LOANS AMORTIZED COST BASIS	53,876	48,344
REVOLVING LOANS CONVERTED TO TERM	664	667
Total loans	284,485	275,939
Performing \| Residential and Consumer \| Residential mortgages
Performing and non-performing outstanding balances of the residential and consumer portfolios
2024/2023	12,877	14,576
2023/2022	15,602	11,620
2022/2021	10,400	61,172
2021/2020	57,540	44,049
2020/2019	41,868	7,092
PRIOR	38,418	35,443
Total loans	176,705	173,952
Performing \| Residential and Consumer \| Consumer
Performing and non-performing outstanding balances of the residential and consumer portfolios
2024/2023	11,476	13,890
2023/2022	10,988	20,430
2022/2021	16,397	9,782
2021/2020	7,605	3,190
2020/2019	2,475	1,169
PRIOR	4,299	4,515
REVOLVING LOANS AMORTIZED COST BASIS	53,876	48,344
REVOLVING LOANS CONVERTED TO TERM	664	667
Total loans	107,780	101,987
Non-performing \| Residential and Consumer
Performing and non-performing outstanding balances of the residential and consumer portfolios
2024/2023		15
2023/2022	110
2022/2021	46
2021/2020		73
2020/2019	59	42
PRIOR	749	998
REVOLVING LOANS AMORTIZED COST BASIS	272	157
REVOLVING LOANS CONVERTED TO TERM		221
Total loans	1,236	1,506
Non-performing \| Residential and Consumer \| Residential mortgages
Performing and non-performing outstanding balances of the residential and consumer portfolios
PRIOR	405	718
Total loans	405	718
Non-performing \| Residential and Consumer \| Consumer
Performing and non-performing outstanding balances of the residential and consumer portfolios
2024/2023		15
2023/2022	110
2022/2021	46
2021/2020		73
2020/2019	59	42
PRIOR	344	280
REVOLVING LOANS AMORTIZED COST BASIS	272	157
REVOLVING LOANS CONVERTED TO TERM		221
Total loans	$ 831	$ 788

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