Allowance for Credit Losses - Non-accrual Basis By Loan Class (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Loan loss allowances, financing receivable past due
Non-accrual loans, total	$ 297,143	$ 140,302
Non-accrual loans with no credit allowance	205,221	78,654
Commercial, financial and agricultural \| Domestic \| Commercial
Loan loss allowances, financing receivable past due
Non-accrual loans, total	205,396	52,397
Non-accrual loans with no credit allowance	177,035	51,513
Commercial, financial and agricultural \| Domestic \| Commercial real estate: farmland & commercial
Loan loss allowances, financing receivable past due
Non-accrual loans, total	43,370	45,066
Non-accrual loans with no credit allowance	21,175	22,003
Commercial, financial and agricultural \| Domestic \| Commercial real estate: multifamily
Loan loss allowances, financing receivable past due
Non-accrual loans, total	44,522	42,787
Non-accrual loans with no credit allowance	6,821	5,086
Commercial real estate \| Domestic \| Commercial real estate construction development
Loan loss allowances, financing receivable past due
Non-accrual loans, total	3,824
Non-accrual loans with no credit allowance	159
Real estate - mortgage \| Domestic \| Residential First Lien
Loan loss allowances, financing receivable past due
Non-accrual loans, total	31	52
Non-accrual loans with no credit allowance	$ 31	$ 52