DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS - Schedule of financial instruments fair value (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2026 USD ($)	Dec. 31, 2025 USD ($)
DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS
Carrying Amount	$ 25,774	$ 25,774
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Fair Value	$ 25,774	$ 25,774
Hierarchy Level	3	3
Deposits
DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS
Carrying Amount	$ 4,445,161	$ 4,482,774
Fair Value	$ 4,442,627	$ 4,480,770
Hierarchy Level	3	3
Short-term borrowings
DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS
Carrying Amount	$ 507,858	$ 379,395
Fair Value	$ 507,858	$ 379,395
Hierarchy Level	3	3
Interest payable
DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS
Carrying Amount	$ 3,250	$ 3,612
Fair Value	$ 3,250	$ 3,612
Hierarchy Level	3	3
Unrecognized financial instruments (net of contractual value) \| Commitments to originate loans
DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS
Hierarchy Level	3	3
Unrecognized financial instruments (net of contractual value) \| Letters of credit
DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS
Carrying Amount	$ 68	$ 53
Fair Value	$ 68	$ 53
Hierarchy Level	3	3
Unrecognized financial instruments (net of contractual value) \| Lines of credit
DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS
Hierarchy Level	3	3
Loans, net of allowance for credit losses
DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS
Carrying Amount	$ 4,456,639	$ 4,356,853
Fair Value	$ 4,374,501	$ 4,261,757
Hierarchy Level	3	3
Cash and cash equivalents
DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS
Carrying Amount	$ 187,404	$ 189,554
Fair Value	$ 187,404	$ 189,554
Hierarchy Level	1	1
Held-to-maturity securities
DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS
Carrying Amount	$ 177,594	$ 179,200
Fair Value	$ 160,520	$ 162,629
Hierarchy Level	2	2
Mortgage loans held for sale
DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS
Carrying Amount	$ 6,823	$ 6,838
Fair Value	$ 6,823	$ 6,838
Hierarchy Level	2	2
Interest receivable
DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS
Carrying Amount	$ 19,716	$ 18,068
Fair Value	$ 19,716	$ 18,068
Hierarchy Level	3	3
Investment in FHLB stock and other assets
DISCLOSURES ABOUT FAIR VALUE OF FINANCIAL INSTRUMENTS
Carrying Amount	$ 27,720	$ 20,079
Fair Value	$ 27,720	$ 20,079
Hierarchy Level	3	3

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