Allowance for Credit Losses - Impairment By Loan Class (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Loan loss allowances
Loans Individually Evaluated for Impairment, Recorded Investment	$ 153,966	$ 169,188
Loans Individually Evaluated for Impairment, Allowance	12,888	18,632
Loans Collectively Evaluated for Impairment, Recorded Investment	9,247,003	8,640,638
Loans Collectively Evaluated for Impairment, Allowance	142,618	137,905
Commercial, financial and agricultural \| Domestic \| Commercial
Loan loss allowances
Loans Individually Evaluated for Impairment, Recorded Investment	52,290	52,110
Loans Individually Evaluated for Impairment, Allowance	400	400
Loans Collectively Evaluated for Impairment, Recorded Investment	1,750,352	1,799,693
Loans Collectively Evaluated for Impairment, Allowance	28,256	29,453
Commercial, financial and agricultural \| Domestic \| Commercial real estate: farmland & commercial
Loan loss allowances
Loans Individually Evaluated for Impairment, Recorded Investment	58,735	65,733
Loans Individually Evaluated for Impairment, Allowance	8,228	8,228
Loans Collectively Evaluated for Impairment, Recorded Investment	3,341,099	2,862,070
Loans Collectively Evaluated for Impairment, Allowance	41,974	35,762
Commercial, financial and agricultural \| Domestic \| Commercial real estate: multifamily
Loan loss allowances
Loans Individually Evaluated for Impairment, Recorded Investment	42,763	42,964
Loans Individually Evaluated for Impairment, Allowance	4,260	1,882
Loans Collectively Evaluated for Impairment, Recorded Investment	579,045	267,151
Loans Collectively Evaluated for Impairment, Allowance	6,480	2,987
Commercial real estate \| Domestic \| Commercial real estate construction development
Loan loss allowances
Loans Individually Evaluated for Impairment, Recorded Investment		8,195
Loans Individually Evaluated for Impairment, Allowance		8,122
Loans Collectively Evaluated for Impairment, Recorded Investment	2,226,013	2,476,259
Loans Collectively Evaluated for Impairment, Allowance	47,046	52,517
Real estate - mortgage \| Domestic \| Residential First Lien
Loan loss allowances
Loans Individually Evaluated for Impairment, Recorded Investment	37	45
Loans Collectively Evaluated for Impairment, Recorded Investment	600,484	530,039
Loans Collectively Evaluated for Impairment, Allowance	6,461	5,528
Real estate - mortgage \| Domestic \| Residential Junior Lien
Loan loss allowances
Loans Individually Evaluated for Impairment, Recorded Investment	141	141
Loans Collectively Evaluated for Impairment, Recorded Investment	456,504	469,088
Loans Collectively Evaluated for Impairment, Allowance	9,820	10,031
Consumer \| Domestic
Loan loss allowances
Loans Collectively Evaluated for Impairment, Recorded Investment	50,741	49,777
Loans Collectively Evaluated for Impairment, Allowance	271	281
Foreign \| Foreign
Loan loss allowances
Loans Collectively Evaluated for Impairment, Recorded Investment	242,765	186,561
Loans Collectively Evaluated for Impairment, Allowance	$ 2,310	$ 1,346

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

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