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FAIR VALUE - Nonreccurring (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	$ 8,173		$ 8,173		$ 8,035
Total Gains (Losses)			0
Net gains (losses) on sales of other real estate owned	(19)	$ 0	(22)	$ 14
Commercial Mortgages
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	6,325		6,325		5,968
Residential Mortgages
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	0		0		0
Consumer Loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	0		0		0
Non-recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	934		934
Non-recurring | Commercial and industrial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	11		11		64
Total Gains (Losses)			0		0
Non-recurring | Commercial mortgages, other | Commercial Mortgages | Commercial mortgages, other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	923		923
Total Gains (Losses)			0
Non-recurring | Other real estate owned:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total other real estate owned, net	483		483		327
Net gains (losses) on sales of other real estate owned			0		0
Non-recurring | Other real estate owned: | Residential Mortgages
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total other real estate owned, net	317		317		116
Net gains (losses) on sales of other real estate owned			0		0
Non-recurring | Other real estate owned: | Consumer Loans | Home equity lines and loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total other real estate owned, net	166		166		211
Net gains (losses) on sales of other real estate owned			0		0
Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	0		0
Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Commercial and industrial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	0		0		0
Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Commercial mortgages, other | Commercial Mortgages | Commercial mortgages, other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	0		0
Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other real estate owned:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total other real estate owned, net	0		0		0
Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other real estate owned: | Residential Mortgages
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total other real estate owned, net	0		0		0
Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) | Other real estate owned: | Consumer Loans | Home equity lines and loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total other real estate owned, net	0		0		0
Non-recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	0		0
Non-recurring | Significant Other Observable Inputs (Level 2) | Commercial and industrial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	0		0		0
Non-recurring | Significant Other Observable Inputs (Level 2) | Commercial mortgages, other | Commercial Mortgages | Commercial mortgages, other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	0		0
Non-recurring | Significant Other Observable Inputs (Level 2) | Other real estate owned:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total other real estate owned, net	0		0		0
Non-recurring | Significant Other Observable Inputs (Level 2) | Other real estate owned: | Residential Mortgages
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total other real estate owned, net	0		0		0
Non-recurring | Significant Other Observable Inputs (Level 2) | Other real estate owned: | Consumer Loans | Home equity lines and loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total other real estate owned, net	0		0		0
Non-recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	934		934
Non-recurring | Significant Unobservable Inputs (Level 3) | Commercial and industrial
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	11		11		64
Non-recurring | Significant Unobservable Inputs (Level 3) | Commercial mortgages, other | Commercial Mortgages | Commercial mortgages, other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Individually analyzed	923		923
Non-recurring | Significant Unobservable Inputs (Level 3) | Other real estate owned:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total other real estate owned, net	483		483		327
Non-recurring | Significant Unobservable Inputs (Level 3) | Other real estate owned: | Residential Mortgages
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total other real estate owned, net	317		317		116
Non-recurring | Significant Unobservable Inputs (Level 3) | Other real estate owned: | Consumer Loans | Home equity lines and loans
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total other real estate owned, net	$ 166		$ 166		$ 211

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