FAIR VALUE MEASUREMENT AND DISCLOSURE (Schedule of Carrying Amounts and Estimated Fair Value for Financial Instrument Assets and Liabilities) (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Financial assets:
Held-to-maturity securities, at amortized cost	$ 495,007	$ 517,778
Held-to-maturity securities, fair value	464,551	470,824
Cash Surrender Value, Fair Value Disclosure	111,299	104,308
Mortgage servicing rights	4,823	4,328
Financial liabilities:
Time deposits	697,249	603,469
Short-term Debt, Fair Value	747,749	500,292
Total short-term borrowings	748,492	500,621
Long-term borrowings	1,000
Junior subordinated debentures	50,724	34,357
Long-term Debt, Fair Value	828
Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	2,076,465	1,569,165
Commercial
Financial assets:
Loans receivable, net of allowance	463,088	365,556
Residential real estate
Financial assets:
Loans receivable, net of allowance	1,731,028	1,494,961
Home equity
Financial assets:
Loans receivable, net of allowance	306,863	241,992
Consumer
Financial assets:
Loans receivable, net of allowance	16,184	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
Long-term Debt, Fair Value	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	464,551	470,824
Cash Surrender Value, Fair Value Disclosure	111,299	104,308
Mortgage servicing rights	0	0
Financial liabilities:
Time deposits	697,249	603,469
Short-term Debt, Fair Value	747,749	500,292
Junior subordinated debentures	50,724	34,357
Long-term Debt, Fair Value	828
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	4,823	4,328
Financial liabilities:
Time deposits	0	0
Short-term Debt, Fair Value	0	0
Junior subordinated debentures	0	0
Long-term Debt, Fair Value	0
Company Determined Fair Value (Level 3) \| Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	2,076,465	1,569,165
Company Determined Fair Value (Level 3) \| Commercial
Financial assets:
Loans receivable, net of allowance	463,088	365,556
Company Determined Fair Value (Level 3) \| Residential real estate
Financial assets:
Loans receivable, net of allowance	1,731,028	1,494,961
Company Determined Fair Value (Level 3) \| Home equity
Financial assets:
Loans receivable, net of allowance	306,863	241,992
Company Determined Fair Value (Level 3) \| Consumer
Financial assets:
Loans receivable, net of allowance	16,184	13,926
Carrying Amount
Financial assets:
Held-to-maturity securities, at amortized cost	495,007	517,778
Cash Surrender Value, Fair Value Disclosure	111,299	104,308
Mortgage servicing rights	2,880	2,119
Financial liabilities:
Time deposits	701,031	607,245
Short-term Debt, Fair Value	493,500	500,621
Junior subordinated debentures	61,441	44,331
Carrying Amount \| Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	2,150,774	1,694,586
Carrying Amount \| Commercial
Financial assets:
Loans receivable, net of allowance	473,689	376,929
Carrying Amount \| Residential real estate
Financial assets:
Loans receivable, net of allowance	2,004,831	1,742,270
Carrying Amount \| Home equity
Financial assets:
Loans receivable, net of allowance	310,188	250,854
Carrying Amount \| Consumer
Financial assets:
Loans receivable, net of allowance	$ 17,944	$ 14,892

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

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