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LOANS AND CREDIT QUALITY - Gross Charge-offs by Year and Type (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Financing Receivable, Credit Quality Indicator [Line Items]
Financing receivable, year one, Gross charge-offs			$ 0
Financing receivable, year two, Gross charge-offs			(61)
Financing receivable, year three, Gross charge-offs			(198)
Financing receivable, year four, Gross charge-offs			0
Financing receivable, year five, Gross charge-offs			(564)
Financing receivable, prior to year five, Gross charge-offs			0
Revolving			(66)
Revolving-term			(50)
Charge-offs	$ (256)	$ (682)	(939)	$ (726)
Consumer loans
Financing Receivable, Credit Quality Indicator [Line Items]
Charge-offs	(90)	(33)	(140)	(66)
Consumer loans \| Home equity and other
Financing Receivable, Credit Quality Indicator [Line Items]
Financing receivable, year one, Gross charge-offs			0
Financing receivable, year two, Gross charge-offs			(61)
Financing receivable, year three, Gross charge-offs			(13)
Financing receivable, year four, Gross charge-offs			0
Financing receivable, year five, Gross charge-offs			0
Financing receivable, prior to year five, Gross charge-offs			0
Revolving			(66)
Revolving-term			0
Charge-offs	(90)	(33)	(140)	(66)
Commercial loans \| Commercial business
Financing Receivable, Credit Quality Indicator [Line Items]
Financing receivable, year one, Gross charge-offs			0
Financing receivable, year two, Gross charge-offs			0
Financing receivable, year three, Gross charge-offs			(185)
Financing receivable, year four, Gross charge-offs			0
Financing receivable, year five, Gross charge-offs			(564)
Financing receivable, prior to year five, Gross charge-offs			0
Revolving			0
Revolving-term			(50)
Charge-offs	$ (166)	$ (649)	$ (799)	$ (660)