LOANS AND RELATED ALLOWANCE FOR CREDIT LOSSES - (Amortized Cost Basis of Loans Nonaccrual Status) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable
Nonaccrual with No Allowance for Credit Loss	$ 4,934
Nonaccrual	18	$ 139
Loans Past Due Greater than 90 Days and Accruing		39
Commercial, Financial and Agricultural \| Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable
Nonaccrual	18
Loans Past Due Greater than 90 Days and Accruing		24
Commercial Loan \| Commercial Portfolio Segment
Accounts, Notes, Loans and Financing Receivable
Nonaccrual with No Allowance for Credit Loss	4,877
Loans Past Due Greater than 90 Days and Accruing		7
Mortgage Loan \| Consumer Portfolio Segment
Accounts, Notes, Loans and Financing Receivable
Nonaccrual with No Allowance for Credit Loss	$ 57
Nonaccrual		139
Loans Past Due Greater than 90 Days and Accruing		4
Personal Loan \| Consumer Portfolio Segment
Accounts, Notes, Loans and Financing Receivable
Loans Past Due Greater than 90 Days and Accruing		$ 4

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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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