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Allowance for Credit Losses (Aging By Loan Class) (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 31, 2022
Financing receivable recorded investment
Past due 90 days or Greater and Still Accruing	$ 4,413	$ 6,132
Loans	7,573,077	7,430,603
Current
Financing receivable recorded investment
Loans	7,504,603	7,412,585
Total Past Due
Financing receivable recorded investment
Loans	68,474	18,018
30 to 59 Days
Financing receivable recorded investment
Loans	20,951	8,552
60 to 89 Days
Financing receivable recorded investment
Loans	3,092	2,251
90 Days or Greater
Financing receivable recorded investment
Loans	44,431	7,215
Commercial, financial and agricultural
Financing receivable recorded investment
Loans	4,280,036	4,373,373
Commercial, financial and agricultural | Domestic | Commercial.
Financing receivable recorded investment
Past due 90 days or Greater and Still Accruing	167	59
Loans	1,453,197	1,498,754
Commercial, financial and agricultural | Domestic | Commercial. | Current
Financing receivable recorded investment
Loans	1,407,227	1,495,750
Commercial, financial and agricultural | Domestic | Commercial. | Total Past Due
Financing receivable recorded investment
Loans	45,970	3,004
Commercial, financial and agricultural | Domestic | Commercial. | 30 to 59 Days
Financing receivable recorded investment
Loans	14,411	1,732
Commercial, financial and agricultural | Domestic | Commercial. | 60 to 89 Days
Financing receivable recorded investment
Loans	1,584	258
Commercial, financial and agricultural | Domestic | Commercial. | 90 Days or Greater
Financing receivable recorded investment
Loans	29,975	1,014
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial
Financing receivable recorded investment
Loans	2,518,670	2,568,118
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Current
Financing receivable recorded investment
Loans	2,517,925	2,566,257
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Total Past Due
Financing receivable recorded investment
Loans	745	1,861
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | 30 to 59 Days
Financing receivable recorded investment
Loans	745	1,744
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | 60 to 89 Days
Financing receivable recorded investment
Loans		117
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily
Financing receivable recorded investment
Loans	308,169	306,501
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | Current
Financing receivable recorded investment
Loans	308,016	306,501
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | Total Past Due
Financing receivable recorded investment
Loans	153
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | 30 to 59 Days
Financing receivable recorded investment
Loans	45
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | 60 to 89 Days
Financing receivable recorded investment
Loans	108
Obligations of states and political subdivisions
Financing receivable recorded investment
Loans	2,202,187	1,989,669
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development
Financing receivable recorded investment
Loans	2,202,187	1,989,669
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | Current
Financing receivable recorded investment
Loans	2,191,375	1,988,539
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | Total Past Due
Financing receivable recorded investment
Loans	10,812	1,130
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | 30 to 59 Days
Financing receivable recorded investment
Loans	629	1,130
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | 60 to 89 Days
Financing receivable recorded investment
Loans	98
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | 90 Days or Greater
Financing receivable recorded investment
Loans	10,085
Real estate - mortgage
Financing receivable recorded investment
Loans	866,427	865,994
Real estate - mortgage | Domestic | Residential: first lien
Financing receivable recorded investment
Past due 90 days or Greater and Still Accruing	2,588	4,061
Loans	418,902	425,724
Real estate - mortgage | Domestic | Residential: first lien | Current
Financing receivable recorded investment
Loans	412,093	418,444
Real estate - mortgage | Domestic | Residential: first lien | Total Past Due
Financing receivable recorded investment
Loans	6,809	7,280
Real estate - mortgage | Domestic | Residential: first lien | 30 to 59 Days
Financing receivable recorded investment
Loans	3,338	2,023
Real estate - mortgage | Domestic | Residential: first lien | 60 to 89 Days
Financing receivable recorded investment
Loans	758	1,068
Real estate - mortgage | Domestic | Residential: first lien | 90 Days or Greater
Financing receivable recorded investment
Loans	2,713	4,189
Real estate - mortgage | Domestic | Residential Junior Lien
Financing receivable recorded investment
Past due 90 days or Greater and Still Accruing	1,278	1,717
Loans	447,525	440,270
Real estate - mortgage | Domestic | Residential Junior Lien | Current
Financing receivable recorded investment
Loans	444,604	436,857
Real estate - mortgage | Domestic | Residential Junior Lien | Total Past Due
Financing receivable recorded investment
Loans	2,921	3,413
Real estate - mortgage | Domestic | Residential Junior Lien | 30 to 59 Days
Financing receivable recorded investment
Loans	1,344	925
Real estate - mortgage | Domestic | Residential Junior Lien | 60 to 89 Days
Financing receivable recorded investment
Loans	299	771
Real estate - mortgage | Domestic | Residential Junior Lien | 90 Days or Greater
Financing receivable recorded investment
Loans	1,278	1,717
Consumer
Financing receivable recorded investment
Loans	43,411	41,592
Consumer | Domestic
Financing receivable recorded investment
Past due 90 days or Greater and Still Accruing	6	7
Loans	43,411	41,592
Consumer | Domestic | Current
Financing receivable recorded investment
Loans	43,131	41,290
Consumer | Domestic | Total Past Due
Financing receivable recorded investment
Loans	280	302
Consumer | Domestic | 30 to 59 Days
Financing receivable recorded investment
Loans	255	281
Consumer | Domestic | 60 to 89 Days
Financing receivable recorded investment
Loans	19	14
Consumer | Domestic | 90 Days or Greater
Financing receivable recorded investment
Loans	6	7
Foreign.
Financing receivable recorded investment
Loans	181,016	159,975
Foreign. | Foreign
Financing receivable recorded investment
Past due 90 days or Greater and Still Accruing	374	288
Loans	181,016	159,975
Foreign. | Foreign | Current
Financing receivable recorded investment
Loans	180,232	158,947
Foreign. | Foreign | Total Past Due
Financing receivable recorded investment
Loans	784	1,028
Foreign. | Foreign | 30 to 59 Days
Financing receivable recorded investment
Loans	184	717
Foreign. | Foreign | 60 to 89 Days
Financing receivable recorded investment
Loans	226	23
Foreign. | Foreign | 90 Days or Greater
Financing receivable recorded investment
Loans	$ 374	$ 288

X

- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
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-Name Accounting Standards Codification
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