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, 2024	Dec. 31, 2023
Financial assets:
Held-to-maturity securities, at amortized cost	$ 526,251	$ 544,931
Held-to-maturity securities, fair value	500,619	510,595
Mortgage servicing rights	3,929	4,124
Financial liabilities:
Time deposits	625,516	634,856
Short-term Debt, Fair Value	515,978	484,849
Junior subordinated debentures	33,248	31,918
Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	1,594,862	1,540,327
Commercial
Financial assets:
Loans receivable, net of allowance	368,193	385,585
Residential real estate
Financial assets:
Loans receivable, net of allowance	1,516,218	1,488,248
Home equity
Financial assets:
Loans receivable, net of allowance	241,323	233,025
Consumer
Financial assets:
Loans receivable, net of allowance	14,282	15,279
Readily Available Market Prices (Level 1)
Financial assets:
Held-to-maturity securities, fair value	0	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	500,619	510,595
Mortgage servicing rights	0	0
Financial liabilities:
Time deposits	625,516	634,856
Short-term Debt, Fair Value	515,978	484,849
Junior subordinated debentures	33,248	31,918
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
Mortgage servicing rights	3,929	4,124
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	1,594,862	1,540,327
Company Determined Fair Value (Level 3) \| Commercial
Financial assets:
Loans receivable, net of allowance	368,193	385,585
Company Determined Fair Value (Level 3) \| Residential real estate
Financial assets:
Loans receivable, net of allowance	1,516,218	1,488,248
Company Determined Fair Value (Level 3) \| Home equity
Financial assets:
Loans receivable, net of allowance	241,323	233,025
Company Determined Fair Value (Level 3) \| Consumer
Financial assets:
Loans receivable, net of allowance	14,282	15,279
Carrying Amount
Financial assets:
Held-to-maturity securities, at amortized cost	526,251	544,931
Mortgage servicing rights	2,146	2,274
Financial liabilities:
Time deposits	628,481	640,539
Short-term Debt, Fair Value	516,336	485,607
Junior subordinated debentures	44,331	44,331
Carrying Amount \| Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	1,689,775	1,653,435
Carrying Amount \| Commercial
Financial assets:
Loans receivable, net of allowance	377,706	399,032
Carrying Amount \| Residential real estate
Financial assets:
Loans receivable, net of allowance	1,752,954	1,753,124
Carrying Amount \| Home equity
Financial assets:
Loans receivable, net of allowance	245,680	238,124
Carrying Amount \| Consumer
Financial assets:
Loans receivable, net of allowance	$ 15,200	$ 17,444

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

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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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