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Allowance for Credit Losses (Non-accrual Basis By Loan Class) (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Loan loss allowances, financing receivable past due
Non-accrual loans, total	$ 41,997	$ 51,648
Commercial, financial and agricultural | Domestic | Commercial.
Loan loss allowances, financing receivable past due
Non-accrual loans, total	31,269	30,747
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial
Loan loss allowances, financing receivable past due
Non-accrual loans, total	298	94
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily
Loan loss allowances, financing receivable past due
Non-accrual loans, total	100	117
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development
Loan loss allowances, financing receivable past due
Non-accrual loans, total	10,087	20,483
Real estate - mortgage | Domestic | Residential: first lien
Loan loss allowances, financing receivable past due
Non-accrual loans, total	$ 243	$ 207

X

- Definition

Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

+ References

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-Topic 326
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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+ References

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