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Allowance for Credit Losses - Non-accrual Basis By Loan Class (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Loan loss allowances, financing receivable past due
Non-accrual loans, total	$ 153,882	$ 169,136
Non-accrual loans with no credit allowance	76,871	76,313
Commercial, financial and agricultural | Domestic | Commercial
Loan loss allowances, financing receivable past due
Non-accrual loans, total	52,290	52,110
Non-accrual loans with no credit allowance	51,670	51,276
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial
Loan loss allowances, financing receivable past due
Non-accrual loans, total	58,735	65,733
Non-accrual loans with no credit allowance	20,045	24,757
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily
Loan loss allowances, financing receivable past due
Non-accrual loans, total	42,763	42,964
Non-accrual loans with no credit allowance	5,062	73
Commercial real estate | Domestic | Commercial real estate construction development
Loan loss allowances, financing receivable past due
Non-accrual loans, total		8,195
Non-accrual loans with no credit allowance		73
Real estate - mortgage | Domestic | Residential First Lien
Loan loss allowances, financing receivable past due
Non-accrual loans, total	94	134
Non-accrual loans with no credit allowance	$ 94	$ 134

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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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