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Allowance for Credit Losses - Non-accrual Basis By Loan Class (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Loan loss allowances, financing receivable past due
Non-accrual loans, total	$ 102,139	$ 47,170
Commercial, financial and agricultural | Domestic | Commercial.
Loan loss allowances, financing receivable past due
Non-accrual loans, total	1,377	30,872
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial
Loan loss allowances, financing receivable past due
Non-accrual loans, total	51,915	299
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily
Loan loss allowances, financing receivable past due
Non-accrual loans, total	38,645	96
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	10,029	15,701
Real estate - mortgage | Domestic | Residential: first lien
Loan loss allowances, financing receivable past due
Non-accrual loans, total	$ 173	$ 202

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

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