FAIR VALUE MEASUREMENT AND DISCLOSURE (Schedule of Carrying Amounts and Estimated Fair Value for Financial Instrument Assets and Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Financial assets:
Held-to-maturity securities, at amortized cost	$ 509,298	$ 517,778
Held-to-maturity securities, fair value	471,195	470,824
Cash Surrender Value, Fair Value Disclosure	110,342	104,308
Mortgage servicing rights	4,968	4,328
Financial liabilities:
Time deposits	768,918	603,469
Short-term Debt, Fair Value	598,869	500,292
Junior subordinated debentures	49,433	34,357
Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	1,988,552	1,569,165
Commercial
Financial assets:
Loans receivable, net of allowance	480,452	365,556
Residential real estate
Financial assets:
Loans receivable, net of allowance	1,707,514	1,494,961
Home equity
Financial assets:
Loans receivable, net of allowance	290,913	241,992
Consumer
Financial assets:
Loans receivable, net of allowance	16,148	13,926
Readily Available Market Prices (Level 1)
Financial assets:
Held-to-maturity securities, fair value	0	0
Cash Surrender Value, Fair Value Disclosure	0
Mortgage servicing rights	0	0
Financial liabilities:
Time deposits	0	0
Short-term Debt, Fair Value	0	0
Junior subordinated debentures	0	0
Readily Available Market Prices (Level 1) \| Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	0	0
Readily Available Market Prices (Level 1) \| Commercial
Financial assets:
Loans receivable, net of allowance	0	0
Readily Available Market Prices (Level 1) \| Residential real estate
Financial assets:
Loans receivable, net of allowance	0	0
Readily Available Market Prices (Level 1) \| Home equity
Financial assets:
Loans receivable, net of allowance	0	0
Readily Available Market Prices (Level 1) \| Consumer
Financial assets:
Loans receivable, net of allowance	0	0
Observable Market Data (Level 2)
Financial assets:
Held-to-maturity securities, fair value	471,195	470,824
Cash Surrender Value, Fair Value Disclosure	110,342	104,308
Mortgage servicing rights	0	0
Financial liabilities:
Time deposits	768,918	603,469
Short-term Debt, Fair Value	598,869	500,292
Junior subordinated debentures	49,433	34,357
Observable Market Data (Level 2) \| Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	0	0
Observable Market Data (Level 2) \| Commercial
Financial assets:
Loans receivable, net of allowance	0	0
Observable Market Data (Level 2) \| Residential real estate
Financial assets:
Loans receivable, net of allowance	0	0
Observable Market Data (Level 2) \| Home equity
Financial assets:
Loans receivable, net of allowance	0	0
Observable Market Data (Level 2) \| Consumer
Financial assets:
Loans receivable, net of allowance	0	0
Company Determined Fair Value (Level 3)
Financial assets:
Held-to-maturity securities, fair value	0	0
Cash Surrender Value, Fair Value Disclosure	0	0
Mortgage servicing rights	4,968	4,328
Financial liabilities:
Time deposits	0	0
Short-term Debt, Fair Value	0	0
Junior subordinated debentures	0	0
Company Determined Fair Value (Level 3) \| Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	1,988,552	1,569,165
Company Determined Fair Value (Level 3) \| Commercial
Financial assets:
Loans receivable, net of allowance	480,452	365,556
Company Determined Fair Value (Level 3) \| Residential real estate
Financial assets:
Loans receivable, net of allowance	1,707,514	1,494,961
Company Determined Fair Value (Level 3) \| Home equity
Financial assets:
Loans receivable, net of allowance	290,913	241,992
Company Determined Fair Value (Level 3) \| Consumer
Financial assets:
Loans receivable, net of allowance	16,148	13,926
Carrying Amount
Financial assets:
Held-to-maturity securities, at amortized cost	509,298	517,778
Cash Surrender Value, Fair Value Disclosure	110,342	104,308
Mortgage servicing rights	2,934	2,119
Financial liabilities:
Time deposits	773,185	607,245
Short-term Debt, Fair Value	599,367	500,621
Junior subordinated debentures	61,365	44,331
Carrying Amount \| Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	2,066,265	1,694,586
Carrying Amount \| Commercial
Financial assets:
Loans receivable, net of allowance	494,808	376,929
Carrying Amount \| Residential real estate
Financial assets:
Loans receivable, net of allowance	2,004,823	1,742,270
Carrying Amount \| Home equity
Financial assets:
Loans receivable, net of allowance	294,398	250,854
Carrying Amount \| Consumer
Financial assets:
Loans receivable, net of allowance	$ 18,053	$ 14,892

Fair value portion of the amount that could be realized under a life insurance contract or contracts owned by the entity, commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

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Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

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