LOANS - Modifications of Loans Performing (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	$ 0
Recorded Investment	3,036,732	$ 3,123,678
Allowance for loan losses, Current Loans	62	163
Allowance for loan losses, Past Due 30-89		29
Allowance for loan losses, Non-Accrual	2,927	3,936
Allowance for loan losses, Total	2,989	4,128
TDRs [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	5,934	6,201
Past Due 30-89		321
Nonaccrual	15,562	21,002
Recorded Investment	21,496	27,524
Commercial financial and agriculture \| TDRs [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	41	59
Nonaccrual	149	765
Recorded Investment	190	824
Commercial real estate \| TDRs [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	3,502	4,560
Past Due 30-89		49
Nonaccrual	13,376	18,076
Recorded Investment	16,878	22,685
Consumer real estate \| TDRs [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	2,371	1,559
Past Due 30-89		269
Nonaccrual	2,037	2,161
Recorded Investment	4,408	3,989
Consumer installment \| TDRs [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	20	23
Past Due 30-89		3
Recorded Investment	$ 20	$ 26

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Financing receivable allowance for credit losses current nonaccrual status.

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Financing receivable allowance for credit losses past due thirty to eighty nine days past due.

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Financing Receivable, Recorded Investment, 30 to 89 Days Past Due

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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