LOANS AND ALLOWANCE FOR CREDIT LOSSES ON LOANS (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from the sale of mortgage loans	$ 42,320	$ 41,913
Gain on sale of mortgage loans	(497)	(470)
Loans held for sale, at fair value (book value of $11,035 and $10,923, respectively)	$ 11,059		$ 11,049
Other industry exposures	0
Non-Accrual Loans	$ 7,251		4,829
Loans outstanding	4,885,086		4,115,259
Loans and Leases Receivable, Excluded Accrued Interest from Amortized Cost	15,800		12,700
FHLB advances, general debt obligations, pledged collateral	1,900,000		1,900,000
Loans And Leases Receivable Impaired Interest Income Foregone	73	43
Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Proceeds from the sale of mortgage loans	42,300	41,400
Gain on sale of mortgage loans	(497)	(470)
Loans held for sale, at fair value (book value of $11,035 and $10,923, respectively)	11,000		10,900
Unrealized gain (loss) on loans held for sale	24		126
Non-Accrual Loans	4,322		1,891
Loans outstanding	2,028,062		1,752,249
Mortgage Loans in Process of Foreclosure, Amount	439		1,000
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Period Increase (Decrease)	102	$ 85
Commercial real estate - non-owner-occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-Accrual Loans	128		129
Loans outstanding	1,685,852		1,387,252
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-Accrual Loans	1,803		1,927
Loans outstanding	487,409		382,785
Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-Accrual Loans	848		434
Loans outstanding	283,491		253,251
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Non-Accrual Loans	7		18
Loans outstanding	$ 19,026		$ 15,010
Non-Residential Building Operators Industry Sector \| Loan Concentration Risk \| Total Loan Portfolio
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk (percentage)	13.00%
Non-Residential Building Operators Industry Sector \| Loan Concentration Risk \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk (percentage)	32.00%
Residential Building Operators Industry Sector \| Loan Concentration Risk \| Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration risk (percentage)	31.00%

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Number of Portfolio Concentration Industries

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Unrealized gain (loss) on loans held for sale

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Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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