Allowance for Credit Losses - Impairment By Loan Class (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Loan loss allowances
Loans Individually Evaluated for Impairment, Recorded Investment	$ 297,134	$ 140,281
Loans Individually Evaluated for Impairment, Allowance	25,210	15,100
Loans Collectively Evaluated for Impairment, Recorded Investment	9,566,065	9,320,141
Loans Collectively Evaluated for Impairment, Allowance	144,804	144,074
Commercial, financial and agricultural \| Domestic \| Commercial
Loan loss allowances
Loans Individually Evaluated for Impairment, Recorded Investment	205,396	52,397
Loans Individually Evaluated for Impairment, Allowance	9,110	500
Loans Collectively Evaluated for Impairment, Recorded Investment	1,537,957	1,683,346
Loans Collectively Evaluated for Impairment, Allowance	25,901	27,429
Commercial, financial and agricultural \| Domestic \| Commercial real estate: farmland & commercial
Loan loss allowances
Loans Individually Evaluated for Impairment, Recorded Investment	43,370	45,066
Loans Individually Evaluated for Impairment, Allowance	7,000	7,000
Loans Collectively Evaluated for Impairment, Recorded Investment	3,256,778	3,137,903
Loans Collectively Evaluated for Impairment, Allowance	40,016	39,413
Commercial, financial and agricultural \| Domestic \| Commercial real estate: multifamily
Loan loss allowances
Loans Individually Evaluated for Impairment, Recorded Investment	44,522	42,787
Loans Individually Evaluated for Impairment, Allowance	8,100	7,600
Loans Collectively Evaluated for Impairment, Recorded Investment	948,773	642,006
Loans Collectively Evaluated for Impairment, Allowance	10,255	7,113
Commercial real estate \| Domestic \| Commercial real estate construction development
Loan loss allowances
Loans Individually Evaluated for Impairment, Recorded Investment	3,824
Loans Individually Evaluated for Impairment, Allowance	1,000
Loans Collectively Evaluated for Impairment, Recorded Investment	2,275,657	2,338,593
Loans Collectively Evaluated for Impairment, Allowance	47,563	48,907
Real estate - mortgage \| Domestic \| Residential First Lien
Loan loss allowances
Loans Individually Evaluated for Impairment, Recorded Investment	22	31
Loans Collectively Evaluated for Impairment, Recorded Investment	662,764	629,403
Loans Collectively Evaluated for Impairment, Allowance	7,034	6,725
Real estate - mortgage \| Domestic \| Residential Junior Lien
Loan loss allowances
Loans Collectively Evaluated for Impairment, Recorded Investment	432,215	445,076
Loans Collectively Evaluated for Impairment, Allowance	8,929	9,420
Consumer \| Domestic
Loan loss allowances
Loans Collectively Evaluated for Impairment, Recorded Investment	50,120	51,003
Loans Collectively Evaluated for Impairment, Allowance	251	279
Foreign \| Foreign
Loan loss allowances
Loans Collectively Evaluated for Impairment, Recorded Investment	401,801	392,811
Loans Collectively Evaluated for Impairment, Allowance	$ 4,855	$ 4,788

Amount of allowance for credit loss on financing receivable evaluated on collective basis. Excludes financing receivable evaluated on individual basis.

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