GOODWILL AND OTHER INTANGIBLES - Goodwill (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
GOODWILL AND OTHER INTANGIBLES
Goodwill, Beginning Balance	$ 141,819	$ 119,477
Acquisition		22,342
Goodwill, Ending Balance	141,819	$ 141,819
Guaranty Bancorp, Inc.
GOODWILL AND OTHER INTANGIBLES
Acquisition	$ 22,300

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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+ Details

BAR HARBOR BANKSHARES 10-Q