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FAIR VALUE - Level 3 Non-Recurring Fair Value Measurement (Details) - Non-recurring - Fair Value, Inputs, Level 3 - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value disclosure	$ 934
Commercial and industrial
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value disclosure		$ 64
Commercial and industrial | Net present value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value disclosure	$ 11
Commercial and industrial | Net present value | Minimum | Present value of cash flows
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value inputs, discount to appraised value	42.73%	47.30%
Commercial and industrial | Net present value | Maximum | Present value of cash flows
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value inputs, discount to appraised value	42.73%	56.80%
Commercial and industrial | Net present value | Weighted Average | Present value of cash flows
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value inputs, discount to appraised value	42.73%	54.80%
Commercial mortgages, other | Commercial mortgages, other | Income approach
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value disclosure	$ 923
Commercial mortgages, other | Commercial mortgages, other | Income approach | Minimum | Discount to appraised value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value inputs, discount to appraised value	12.10%
Commercial mortgages, other | Commercial mortgages, other | Income approach | Maximum | Discount to appraised value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value inputs, discount to appraised value	12.10%
Commercial mortgages, other | Commercial mortgages, other | Income approach | Weighted Average | Discount to appraised value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value inputs, discount to appraised value	12.10%
Other real estate owned:
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value disclosure	$ 483	$ 327
Other real estate owned: | Residential mortgages | Sales comparison
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value disclosure	$ 317	$ 116
Other real estate owned: | Residential mortgages | Sales comparison | Minimum | Discount to appraised value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value inputs, discount to appraised value	20.80%	20.80%
Other real estate owned: | Residential mortgages | Sales comparison | Maximum | Discount to appraised value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value inputs, discount to appraised value	20.80%	20.80%
Other real estate owned: | Residential mortgages | Sales comparison | Weighted Average | Discount to appraised value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value inputs, discount to appraised value	20.80%	20.80%
Other real estate owned: | Home equity lines and loans | Sales comparison
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, fair value disclosure	$ 166	$ 211
Other real estate owned: | Home equity lines and loans | Sales comparison | Minimum | Discount to appraised value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value inputs, discount to appraised value	20.80%	20.80%
Other real estate owned: | Home equity lines and loans | Sales comparison | Maximum | Discount to appraised value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value inputs, discount to appraised value	20.80%	20.80%
Other real estate owned: | Home equity lines and loans | Sales comparison | Weighted Average | Discount to appraised value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fair value inputs, discount to appraised value	20.80%	20.80%

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+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482078/820-10-55-100

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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