LOANS - Modifications of Loans Performing (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Financing Receivable, Recorded Investment, Past Due [Line Items]
Recorded Investment	$ 2,960,919	$ 3,123,678
Allowance for loan losses, Past Due 30-89		29
Allowance for loan losses, Non-Accrual	2,872	3,936
Allowance for loan losses, Total	3,007	4,128
Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	0
Allowance for loan losses, Current Loans	135	163
TDRs [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due 30-89	54	321
Nonaccrual	15,245	21,002
Recorded Investment	25,921	27,524
TDRs [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	10,622	6,201
Commercial, financial and agriculture \| TDRs [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Nonaccrual	127	765
Recorded Investment	201	824
Commercial, financial and agriculture \| TDRs [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	74	59
Commercial real estate \| TDRs [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due 30-89		49
Nonaccrual	13,092	18,076
Recorded Investment	21,416	22,685
Commercial real estate \| TDRs [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	8,324	4,560
Consumer real estate \| TDRs [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due 30-89	54	269
Nonaccrual	2,026	2,161
Recorded Investment	4,283	3,989
Consumer real estate \| TDRs [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	2,203	1,559
Consumer Installment \| TDRs [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Past Due 30-89		3
Recorded Investment	21	26
Consumer Installment \| TDRs [Member] \| Financial Asset, Not Past Due [Member]
Financing Receivable, Recorded Investment, Past Due [Line Items]
Current Loans	$ 21	$ 23

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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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