DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES - Consolidated statements of income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ (264)	$ 590	$ (270)	$ 1,934
Designated as hedging instrument \| Economic hedges
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	48	(23)	(19)	12
Designated as hedging instrument \| Economic hedges \| Forward commitments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	48	(23)	(19)	12
Not designated as hedging instrument
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	(127)	1	26	84
Not designated as hedging instrument \| Interest rate lock commitments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Income	$ (127)	$ 1	$ 26	$ 84

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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BAR HARBOR BANKSHARES 10-Q