LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES - (Amortized Cost Basis of Loans Nonaccrual Status) (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable
Nonaccrual with No Allowance for Credit Loss	$ 122	$ 4,934
Nonaccrual	90	18
Loans Past Due Greater than 90 Days and Accruing	35
Commercial, Financial and Agricultural \| Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable
Nonaccrual	90	18
Commercial Loan \| Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable
Nonaccrual with No Allowance for Credit Loss		4,877
Mortgage Loan \| Consumer Portfolio Segment
Accounts, Notes, Loans and Financing Receivable
Nonaccrual with No Allowance for Credit Loss	122	$ 57
Loans Past Due Greater than 90 Days and Accruing	$ 35

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Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

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