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Allowance for Credit Losses - Portfolio Credit Quality (Details) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2024 USD ($) loan | Jun. 30, 2023 USD ($) | Jun. 30, 2024 USD ($) loan item | Jun. 30, 2023 USD ($) | Dec. 31, 2023 USD ($)
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | $ 1,795,967 |  | $ 1,795,967 |  |
2023 | 2,641,349 |  | 2,641,349 |  | $ 3,364,226
2022 | 1,521,378 |  | 1,521,378 |  | 1,928,023
2021 | 1,114,640 |  | 1,114,640 |  | 1,328,045
2020 | 505,853 |  | 505,853 |  | 609,341
2019/Prior | 688,640 |  | 688,640 |  | 295,840
Prior |  |  |  |  | 533,486
Total loans | 8,267,827 |  | 8,267,827 |  | 8,058,961
Current-period gross writeoffs |  |  |  |  |
Total | $ 4,260 | $ 2,982 | $ 32,084 | $ 5,015 |
Commercial. |  |  |  |  |
Current-period gross writeoffs |  |  |  |  |
Number of relationships upgraded to special review | item |  |  | 1 |  |
Commercial real estate: farmland & commercial |  |  |  |  |
Current-period gross writeoffs |  |  |  |  |
Number of loans downgraded | loan | 1 |  | 1 |  |
Commercial real estate: multifamily |  |  |  |  |
Current-period gross writeoffs |  |  |  |  |
Number of loans downgraded | loan | 2 |  | 2 |  |
Number of relationships downgraded from pass | item |  |  | 2 |  |
Commercial, financial and agricultural |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
Total loans | $ 4,769,703 |  | $ 4,769,703 |  | 4,802,622
Commercial, financial and agricultural | Domestic | Commercial. |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 428,315 |  | 428,315 |  |
2023 | 574,007 |  | 574,007 |  | 811,918
2022 | 153,687 |  | 153,687 |  | 305,621
2021 | 290,361 |  | 290,361 |  | 364,498
2020 | 42,125 |  | 42,125 |  | 50,602
2019/Prior | 96,682 |  | 96,682 |  | 21,468
Prior |  |  |  |  | 74,123
Total loans | 1,585,177 |  | 1,585,177 |  | 1,628,230
Current-period gross writeoffs |  |  |  |  |
2024 |  |  | 1,768 |  |
2023 |  |  | 2,288 |  | 7,053
2022 |  |  | 25,620 |  | 2,187
2021 |  |  | 27 |  | 155
2020 |  |  | 14 |  | 264
2019 |  |  |  |  | 2
Prior |  |  | 3 |  |
Prior |  |  |  |  | 3
Total | 1,979 | 2,792 | 29,720 | 4,763 | 9,664
Commercial, financial and agricultural | Domestic | Commercial. | Pass |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 428,054 |  | 428,054 |  |
2023 | 559,120 |  | 559,120 |  | 791,233
2022 | 152,661 |  | 152,661 |  | 272,919
2021 | 290,204 |  | 290,204 |  | 364,271
2020 | 42,125 |  | 42,125 |  | 50,602
2019/Prior | 96,681 |  | 96,681 |  | 21,468
Prior |  |  |  |  | 74,119
Total loans | 1,568,845 |  | 1,568,845 |  | 1,574,612
Commercial, financial and agricultural | Domestic | Commercial. | Special Review |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2023 | 1,872 |  | 1,872 |  | 7,613
2022 |  |  |  |  | 1,800
2021 | 138 |  | 138 |  | 164
Total loans | 2,010 |  | 2,010 |  | 9,577
Commercial, financial and agricultural | Domestic | Commercial. | Watch List - Pass |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2023 | 11,760 |  | 11,760 |  | 11,865
Total loans | 11,760 |  | 11,760 |  | 11,865
Commercial, financial and agricultural | Domestic | Commercial. | Watch List - Substandard |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 183 |  | 183 |  |
2023 | 947 |  | 947 |  | 1,180
2022 | 35 |  | 35 |  | 92
2021 | 19 |  | 19 |  | 28
2019/Prior | 1 |  | 1 |  |
Prior |  |  |  |  | 4
Total loans | 1,185 |  | 1,185 |  | 1,304
Commercial, financial and agricultural | Domestic | Commercial. | Watch List - Doubtful |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 78 |  | 78 |  |
2023 | 308 |  | 308 |  | 27
2022 | 991 |  | 991 |  | 30,810
2021 |  |  |  |  | 35
Total loans | 1,377 |  | 1,377 |  | 30,872
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 512,533 |  | 512,533 |  |
2023 | 811,817 |  | 811,817 |  | 1,040,592
2022 | 581,872 |  | 581,872 |  | 631,029
2021 | 361,231 |  | 361,231 |  | 419,048
2020 | 255,401 |  | 255,401 |  | 270,009
2019/Prior | 344,538 |  | 344,538 |  | 184,248
Prior |  |  |  |  | 248,627
Total loans | 2,867,392 |  | 2,867,392 |  | 2,793,553
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Pass |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 443,421 |  | 443,421 |  |
2023 | 734,880 |  | 734,880 |  | 888,878
2022 | 579,702 |  | 579,702 |  | 628,653
2021 | 361,011 |  | 361,011 |  | 415,458
2020 | 253,124 |  | 253,124 |  | 267,705
2019/Prior | 344,498 |  | 344,498 |  | 184,164
Prior |  |  |  |  | 248,626
Total loans | 2,716,636 |  | 2,716,636 |  | 2,633,484
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Special Review |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 693 |  | 693 |  |
2023 | 68,156 |  | 68,156 |  | 5,205
2021 |  |  |  |  | 3,357
Total loans | 68,849 |  | 68,849 |  | 8,562
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Watch List - Pass |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 16,504 |  | 16,504 |  |
2023 |  |  |  |  | 16,654
2022 |  |  |  |  | 87
2021 | 220 |  | 220 |  | 233
Total loans | 16,724 |  | 16,724 |  | 16,974
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Watch List - Substandard |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2023 | 8,781 |  | 8,781 |  | 129,644
2022 | 2,170 |  | 2,170 |  | 2,201
2020 | 2,277 |  | 2,277 |  | 2,304
2019/Prior | 40 |  | 40 |  | 84
Prior |  |  |  |  | 1
Total loans | 13,268 |  | 13,268 |  | 134,234
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Watch List - Doubtful |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 51,915 |  | 51,915 |  |
2023 |  |  |  |  | 211
2022 |  |  |  |  | 88
Total loans | 51,915 |  | 51,915 |  | 299
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 66,981 |  | 66,981 |  |
2023 | 42,449 |  | 42,449 |  | 123,523
2022 | 90,964 |  | 90,964 |  | 94,647
2021 | 22,517 |  | 22,517 |  | 42,081
2020 | 60,011 |  | 60,011 |  | 73,652
2019/Prior | 34,212 |  | 34,212 |  | 10,743
Prior |  |  |  |  | 36,193
Total loans | 317,134 |  | 317,134 |  | 380,839
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | Pass |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 53,481 |  | 53,481 |  |
2023 | 17,385 |  | 17,385 |  | 123,523
2022 | 90,883 |  | 90,883 |  | 94,551
2021 | 22,517 |  | 22,517 |  | 42,081
2020 | 60,011 |  | 60,011 |  | 73,652
2019/Prior | 34,212 |  | 34,212 |  | 10,743
Prior |  |  |  |  | 36,193
Total loans | 278,489 |  | 278,489 |  | 380,743
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | Watch List - Doubtful |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 13,500 |  | 13,500 |  |
2023 | 25,064 |  | 25,064 |  |
2022 | 81 |  | 81 |  | 96
Total loans | 38,645 |  | 38,645 |  | 96
Obligations of states and political subdivisions |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
Total loans | 2,303,690 |  | 2,303,690 |  | 2,091,622
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 512,464 |  | 512,464 |  |
2023 | 943,077 |  | 943,077 |  | 966,695
2022 | 516,102 |  | 516,102 |  | 687,012
2021 | 276,944 |  | 276,944 |  | 324,238
2020 | 44,154 |  | 44,154 |  | 96,400
2019/Prior | 10,949 |  | 10,949 |  | 14,058
Prior |  |  |  |  | 3,219
Total loans | 2,303,690 |  | 2,303,690 |  | 2,091,622
Current-period gross writeoffs |  |  |  |  |
2023 |  |  | 1,146 |  |
2022 |  |  | 1,082 |  |
Total | 2,228 |  | 2,228 |  |
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | Pass |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 512,208 |  | 512,208 |  |
2023 | 916,247 |  | 916,247 |  | 938,739
2022 | 506,150 |  | 506,150 |  | 674,037
2021 | 276,944 |  | 276,944 |  | 324,238
2020 | 44,154 |  | 44,154 |  | 96,400
2019/Prior | 10,949 |  | 10,949 |  | 14,058
Prior |  |  |  |  | 3,219
Total loans | 2,266,652 |  | 2,266,652 |  | 2,050,691
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | Special Review |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2023 | 17,370 |  | 17,370 |  |
Total loans | 17,370 |  | 17,370 |  |
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | Watch List - Substandard |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 178 |  | 178 |  |
2023 | 9,460 |  | 9,460 |  | 25,230
Total loans | 9,638 |  | 9,638 |  | 25,230
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | Watch List - Doubtful |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 78 |  | 78 |  |
2023 |  |  |  |  | 2,726
2022 | 9,952 |  | 9,952 |  | 12,975
Total loans | 10,030 |  | 10,030 |  | 15,701
Real estate - mortgage |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
Total loans | 967,792 |  | 967,792 |  | 938,901
Real estate - mortgage | Domestic | Residential: first lien |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 122,919 |  | 122,919 |  |
2023 | 113,107 |  | 113,107 |  | 180,127
2022 | 85,681 |  | 85,681 |  | 83,661
2021 | 61,274 |  | 61,274 |  | 68,409
2020 | 31,390 |  | 31,390 |  | 39,935
2019/Prior | 84,279 |  | 84,279 |  | 27,499
Prior |  |  |  |  | 78,401
Total loans | 498,650 |  | 498,650 |  | 478,032
Current-period gross writeoffs |  |  |  |  |
Prior |  |  | 46 |  |
Prior |  |  |  |  | 43
Total | 1 |  | 46 |  | 43
Real estate - mortgage | Domestic | Residential: first lien | Pass |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 122,822 |  | 122,822 |  |
2023 | 113,107 |  | 113,107 |  | 180,127
2022 | 85,626 |  | 85,626 |  | 83,568
2021 | 60,962 |  | 60,962 |  | 68,082
2020 | 31,390 |  | 31,390 |  | 39,935
2019/Prior | 84,279 |  | 84,279 |  | 27,499
Prior |  |  |  |  | 78,306
Total loans | 498,186 |  | 498,186 |  | 477,517
Real estate - mortgage | Domestic | Residential: first lien | Watch List - Substandard |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 97 |  | 97 |  |
2021 | 312 |  | 312 |  | 327
Prior |  |  |  |  | 95
Total loans | 409 |  | 409 |  | 422
Real estate - mortgage | Domestic | Residential: first lien | Watch List - Doubtful |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2022 | 55 |  | 55 |  | 93
Total loans | 55 |  | 55 |  | 93
Real estate - mortgage | Domestic | Residential Junior Lien |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 45,871 |  | 45,871 |  |
2023 | 80,297 |  | 80,297 |  | 88,628
2022 | 69,827 |  | 69,827 |  | 76,845
2021 | 90,926 |  | 90,926 |  | 96,411
2020 | 71,044 |  | 71,044 |  | 76,490
2019/Prior | 111,177 |  | 111,177 |  | 34,870
Prior |  |  |  |  | 87,625
Total loans | 469,142 |  | 469,142 |  | 460,869
Current-period gross writeoffs |  |  |  |  |
Prior |  |  |  |  | 298
Total |  | 164 |  | 165 | 298
Real estate - mortgage | Domestic | Residential Junior Lien | Pass |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 45,871 |  | 45,871 |  |
2023 | 80,297 |  | 80,297 |  | 88,628
2022 | 69,827 |  | 69,827 |  | 76,845
2021 | 90,926 |  | 90,926 |  | 96,411
2020 | 71,044 |  | 71,044 |  | 76,490
2019/Prior | 111,177 |  | 111,177 |  | 34,870
Prior |  |  |  |  | 87,625
Total loans | 469,142 |  | 469,142 |  | 460,869
Consumer |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
Total loans | 46,954 |  | 46,954 |  | 45,121
Consumer | Domestic |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 23,740 |  | 23,740 |  |
2023 | 18,735 |  | 18,735 |  | 36,639
2022 | 2,218 |  | 2,218 |  | 5,366
2021 | 642 |  | 642 |  | 1,043
2020 | 87 |  | 87 |  | 237
2019/Prior | 1,532 |  | 1,532 |  | 157
Prior |  |  |  |  | 1,679
Total loans | 46,954 |  | 46,954 |  | 45,121
Current-period gross writeoffs |  |  |  |  |
2024 |  |  | 4 |  |
2023 |  |  | 66 |  | 54
2022 |  |  | 19 |  | 115
2021 |  |  |  |  | 9
2019 |  |  |  |  | 1
Prior |  |  | 1 |  |
Total | 52 | $ 26 | 90 | $ 87 | 179
Consumer | Domestic | Pass |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 23,740 |  | 23,740 |  |
2023 | 18,735 |  | 18,735 |  | 36,639
2022 | 2,218 |  | 2,218 |  | 5,366
2021 | 642 |  | 642 |  | 1,043
2020 | 87 |  | 87 |  | 237
2019/Prior | 1,532 |  | 1,532 |  | 157
Prior |  |  |  |  | 1,679
Total loans | 46,954 |  | 46,954 |  | 45,121
Foreign. |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
Total loans | 179,688 |  | 179,688 |  | 180,695
Foreign. | Foreign |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 83,144 |  | 83,144 |  |
2023 | 57,860 |  | 57,860 |  | 116,104
2022 | 21,027 |  | 21,027 |  | 43,842
2021 | 10,745 |  | 10,745 |  | 12,317
2020 | 1,641 |  | 1,641 |  | 2,016
2019/Prior | 5,271 |  | 5,271 |  | 2,797
Prior |  |  |  |  | 3,619
Total loans | 179,688 |  | 179,688 |  | 180,695
Foreign. | Foreign | Pass |  |  |  |  |
Loan portfolio by credit quality indicator |  |  |  |  |
2024 | 83,144 |  | 83,144 |  |
2023 | 57,860 |  | 57,860 |  | 116,104
2022 | 21,027 |  | 21,027 |  | 43,842
2021 | 10,745 |  | 10,745 |  | 12,317
2020 | 1,641 |  | 1,641 |  | 2,016
2019/Prior | 5,271 |  | 5,271 |  | 2,797
Prior |  |  |  |  | 3,619
Total loans | $ 179,688 |  | $ 179,688 |  | $ 180,695

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