ALLOWANCE FOR CREDIT LOSSES - LOANS - Residential and consumer portfolio (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Performing and non-performing outstanding balances of the residential and consumer portfolios
Total loans	$ 1,032,727	$ 1,067,949
Current period gross charge-offs, Total	5,073	2,205
Consumer and Residential mortgages
Performing and non-performing outstanding balances of the residential and consumer portfolios
2025/2024	15,923	24,353
2024/2023	22,500	26,700
2023/2022	23,080	26,843
2022/2021	23,023	65,145
2021/2020	59,453	44,402
Prior	78,515	43,466
Revolving Loans Amortized Cost Basis	60,015	54,148
Revolving Loans Converted to Term	110	664
Total loans	282,619	285,721
Current period gross charge-offs, 2025/2024	1	5
Current period gross charge-offs, 2024/2023	28	6
Current period gross charge-offs, 2023/2022	41	21
Current period gross charge-offs, 2022/2021	8	19
Current period gross charge-offs, 2021/2020	1	13
Current period gross charge-offs, Prior	75	143
Current period gross charge-offs, Total	154	207
Residential mortgages
Performing and non-performing outstanding balances of the residential and consumer portfolios
2025/2024	4,377	12,877
2024/2023	13,914	15,602
2023/2022	15,006	10,400
2022/2021	10,054	57,540
2021/2020	53,633	41,868
Prior	72,830	38,823
Total loans	169,814	177,110
Current period gross charge-offs, Total	0
Consumer
Performing and non-performing outstanding balances of the residential and consumer portfolios
2025/2024	11,546	11,476
2024/2023	8,586	11,098
2023/2022	8,074	16,443
2022/2021	12,969	7,605
2021/2020	5,820	2,534
Prior	5,685	4,643
Revolving Loans Amortized Cost Basis	60,015	54,148
Revolving Loans Converted to Term	110	664
Total loans	112,805	108,611
Current period gross charge-offs, 2025/2024	1	5
Current period gross charge-offs, 2024/2023	28	6
Current period gross charge-offs, 2023/2022	41	21
Current period gross charge-offs, 2022/2021	8	19
Current period gross charge-offs, 2021/2020	1	13
Current period gross charge-offs, Prior	75	143
Current period gross charge-offs, Total	154	207
Performing \| Consumer and Residential mortgages
Performing and non-performing outstanding balances of the residential and consumer portfolios
2025/2024	15,923	24,353
2024/2023	22,495	26,590
2023/2022	23,005	26,797
2022/2021	23,006	65,145
2021/2020	59,298	44,343
Prior	78,132	42,717
Revolving Loans Amortized Cost Basis	59,823	53,876
Revolving Loans Converted to Term	110	664
Total loans	281,792	284,485
Performing \| Residential mortgages
Performing and non-performing outstanding balances of the residential and consumer portfolios
2025/2024	4,377	12,877
2024/2023	13,914	15,602
2023/2022	15,006	10,400
2022/2021	10,054	57,540
2021/2020	53,478	41,868
Prior	72,769	38,418
Total loans	169,598	176,705
Performing \| Consumer
Performing and non-performing outstanding balances of the residential and consumer portfolios
2025/2024	11,546	11,476
2024/2023	8,581	10,988
2023/2022	7,999	16,397
2022/2021	12,952	7,605
2021/2020	5,820	2,475
Prior	5,363	4,299
Revolving Loans Amortized Cost Basis	59,823	53,876
Revolving Loans Converted to Term	110	664
Total loans	112,194	107,780
Non-performing \| Consumer and Residential mortgages
Performing and non-performing outstanding balances of the residential and consumer portfolios
2024/2023	5	110
2023/2022	75	46
2022/2021	17
2021/2020	155	59
Prior	383	749
Revolving Loans Amortized Cost Basis	192	272
Total loans	827	1,236
Non-performing \| Residential mortgages
Performing and non-performing outstanding balances of the residential and consumer portfolios
2021/2020	155
Prior	61	405
Total loans	216	405
Non-performing \| Consumer
Performing and non-performing outstanding balances of the residential and consumer portfolios
2024/2023	5	110
2023/2022	75	46
2022/2021	17
2021/2020		59
Prior	322	344
Revolving Loans Amortized Cost Basis	192	272
Total loans	$ 611	$ 831

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