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, 2023	Dec. 31, 2022
Financial assets:
Held-to-maturity securities, at amortized cost	$ 549,961	$ 546,583
Held-to-maturity securities, fair value	483,547	506,193
Mortgage servicing rights	4,321	4,412
Financial liabilities:
Time deposits	609,195	291,568
Short-term Debt, Fair Value	469,103	264,779
Junior subordinated debentures	31,475	31,032
Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	1,532,605	1,550,379
Commercial
Financial assets:
Loans receivable, net of allowance	379,502	414,353
Residential real estate
Financial assets:
Loans receivable, net of allowance	1,460,556	1,494,707
Home equity
Financial assets:
Loans receivable, net of allowance	228,878	237,967
Consumer
Financial assets:
Loans receivable, net of allowance	16,385	17,853
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	483,547	506,193
Mortgage servicing rights	0	0
Financial liabilities:
Time deposits	609,195	291,568
Short-term Debt, Fair Value	469,103	264,779
Junior subordinated debentures	31,475	31,032
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	4,321	4,412
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	1,532,605	1,550,379
Company Determined Fair Value (Level 3) \| Commercial
Financial assets:
Loans receivable, net of allowance	379,502	414,353
Company Determined Fair Value (Level 3) \| Residential real estate
Financial assets:
Loans receivable, net of allowance	1,460,556	1,494,707
Company Determined Fair Value (Level 3) \| Home equity
Financial assets:
Loans receivable, net of allowance	228,878	237,967
Company Determined Fair Value (Level 3) \| Consumer
Financial assets:
Loans receivable, net of allowance	16,385	17,853
Carrying Amount
Financial assets:
Held-to-maturity securities, at amortized cost	549,961	546,583
Mortgage servicing rights	2,316	2,458
Financial liabilities:
Time deposits	617,609	300,451
Short-term Debt, Fair Value	470,140	265,176
Junior subordinated debentures	44,331	44,331
Carrying Amount \| Commercial Real Estate
Financial assets:
Loans receivable, net of allowance	1,634,347	1,605,279
Carrying Amount \| Commercial
Financial assets:
Loans receivable, net of allowance	395,549	424,685
Carrying Amount \| Residential real estate
Financial assets:
Loans receivable, net of allowance	1,742,359	1,691,177
Carrying Amount \| Home equity
Financial assets:
Loans receivable, net of allowance	231,155	232,203
Carrying Amount \| Consumer
Financial assets:
Loans receivable, net of allowance	$ 18,596	$ 20,087

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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