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Allowance for Credit Losses - Aging By Loan Class (Details) $ in Thousands	Sep. 30, 2025 USD ($) loan	Dec. 31, 2024 USD ($) loan
Financing receivable recorded investment
Past due 90 days or Greater and Still Accruing	$ 55,000	$ 6,693
Loans	9,400,969	8,809,826
Current
Financing receivable recorded investment
Loans	9,230,140	8,670,880
Total Past Due
Financing receivable recorded investment
Loans	170,829	138,946
30 to 59 Days
Financing receivable recorded investment
Loans	23,455	16,012
60 to 89 Days
Financing receivable recorded investment
Loans	9,075	56,767
90 Days or Greater
Financing receivable recorded investment
Loans	$ 138,299	$ 66,167
Commercial
Financing receivable recorded investment
Number of loans placed on non-accrual | loan		3
Commercial | Commercial properties
Financing receivable recorded investment
Number of loans placed on non-accrual | loan		2
Commercial | Aircraft
Financing receivable recorded investment
Number of loans placed on non-accrual | loan		1
Commercial real estate: farmland & commercial
Financing receivable recorded investment
Number of Loans Secured by Hotel | loan	2
Commercial, financial and agricultural
Financing receivable recorded investment
Loans	$ 5,824,284	$ 5,089,721
Commercial, financial and agricultural | Domestic | Commercial
Financing receivable recorded investment
Past due 90 days or Greater and Still Accruing	43,026	534
Loans	1,802,642	1,851,803
Commercial, financial and agricultural | Domestic | Commercial | Current
Financing receivable recorded investment
Loans	1,706,748	1,795,577
Commercial, financial and agricultural | Domestic | Commercial | Total Past Due
Financing receivable recorded investment
Loans	95,894	56,226
Commercial, financial and agricultural | Domestic | Commercial | 30 to 59 Days
Financing receivable recorded investment
Loans	5,332	4,070
Commercial, financial and agricultural | Domestic | Commercial | 60 to 89 Days
Financing receivable recorded investment
Loans	574	51,577
Commercial, financial and agricultural | Domestic | Commercial | 90 Days or Greater
Financing receivable recorded investment
Loans	89,988	579
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial
Financing receivable recorded investment
Past due 90 days or Greater and Still Accruing	3,819	262
Loans	3,399,834	2,927,803
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Current
Financing receivable recorded investment
Loans	3,357,512	2,900,166
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Total Past Due
Financing receivable recorded investment
Loans	42,322	27,637
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | 30 to 59 Days
Financing receivable recorded investment
Loans	1,382	1,221
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | 60 to 89 Days
Financing receivable recorded investment
Loans	840
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | 90 Days or Greater
Financing receivable recorded investment
Loans	40,100	26,416
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily
Financing receivable recorded investment
Loans	621,808	310,115
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | Current
Financing receivable recorded investment
Loans	621,479	284,781
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | Total Past Due
Financing receivable recorded investment
Loans	329	25,334
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | 30 to 59 Days
Financing receivable recorded investment
Loans	329
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | 60 to 89 Days
Financing receivable recorded investment
Loans		270
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | 90 Days or Greater
Financing receivable recorded investment
Loans		25,064
Commercial real estate
Financing receivable recorded investment
Loans	2,226,013	2,484,454
Commercial real estate | Domestic | Commercial real estate construction development
Financing receivable recorded investment
Past due 90 days or Greater and Still Accruing	1,198
Loans	2,226,013	2,484,454
Commercial real estate | Domestic | Commercial real estate construction development | Current
Financing receivable recorded investment
Loans	2,220,290	2,473,896
Commercial real estate | Domestic | Commercial real estate construction development | Total Past Due
Financing receivable recorded investment
Loans	5,723	10,558
Commercial real estate | Domestic | Commercial real estate construction development | 30 to 59 Days
Financing receivable recorded investment
Loans	3,711	2,421
Commercial real estate | Domestic | Commercial real estate construction development | 60 to 89 Days
Financing receivable recorded investment
Loans	814	15
Commercial real estate | Domestic | Commercial real estate construction development | 90 Days or Greater
Financing receivable recorded investment
Loans	1,198	8,122
Real estate - mortgage
Financing receivable recorded investment
Loans	1,057,166	999,313
Real estate - mortgage | Domestic | Residential First Lien
Financing receivable recorded investment
Past due 90 days or Greater and Still Accruing	3,655	3,542
Loans	600,521	530,084
Real estate - mortgage | Domestic | Residential First Lien | Current
Financing receivable recorded investment
Loans	584,984	520,353
Real estate - mortgage | Domestic | Residential First Lien | Total Past Due
Financing receivable recorded investment
Loans	15,537	9,731
Real estate - mortgage | Domestic | Residential First Lien | 30 to 59 Days
Financing receivable recorded investment
Loans	8,918	4,763
Real estate - mortgage | Domestic | Residential First Lien | 60 to 89 Days
Financing receivable recorded investment
Loans	2,908	1,337
Real estate - mortgage | Domestic | Residential First Lien | 90 Days or Greater
Financing receivable recorded investment
Loans	3,711	3,631
Real estate - mortgage | Domestic | Residential Junior Lien
Financing receivable recorded investment
Past due 90 days or Greater and Still Accruing	3,080	2,000
Loans	456,645	469,229
Real estate - mortgage | Domestic | Residential Junior Lien | Current
Financing receivable recorded investment
Loans	450,017	463,086
Real estate - mortgage | Domestic | Residential Junior Lien | Total Past Due
Financing receivable recorded investment
Loans	6,628	6,143
Real estate - mortgage | Domestic | Residential Junior Lien | 30 to 59 Days
Financing receivable recorded investment
Loans	2,377	2,599
Real estate - mortgage | Domestic | Residential Junior Lien | 60 to 89 Days
Financing receivable recorded investment
Loans	1,171	1,544
Real estate - mortgage | Domestic | Residential Junior Lien | 90 Days or Greater
Financing receivable recorded investment
Loans	3,080	2,000
Consumer
Financing receivable recorded investment
Loans	50,741	49,777
Consumer | Domestic
Financing receivable recorded investment
Past due 90 days or Greater and Still Accruing	27	16
Loans	50,741	49,777
Consumer | Domestic | Current
Financing receivable recorded investment
Loans	50,450	49,607
Consumer | Domestic | Total Past Due
Financing receivable recorded investment
Loans	291	170
Consumer | Domestic | 30 to 59 Days
Financing receivable recorded investment
Loans	234	122
Consumer | Domestic | 60 to 89 Days
Financing receivable recorded investment
Loans	30	32
Consumer | Domestic | 90 Days or Greater
Financing receivable recorded investment
Loans	27	16
Foreign
Financing receivable recorded investment
Loans	242,765	186,561
Foreign | Foreign
Financing receivable recorded investment
Past due 90 days or Greater and Still Accruing	195	339
Loans	242,765	186,561
Foreign | Foreign | Current
Financing receivable recorded investment
Loans	238,660	183,414
Foreign | Foreign | Total Past Due
Financing receivable recorded investment
Loans	4,105	3,147
Foreign | Foreign | 30 to 59 Days
Financing receivable recorded investment
Loans	1,172	816
Foreign | Foreign | 60 to 89 Days
Financing receivable recorded investment
Loans	2,738	1,992
Foreign | Foreign | 90 Days or Greater
Financing receivable recorded investment
Loans	$ 195	$ 339

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