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Allowance for Credit Losses (Portfolio Credit Quality) (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2023 USD ($) item | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Loan portfolio by credit quality indicator |  |  |
2023 | $ 3,364,226 |  |
2022 | 1,928,023 | $ 3,048,975 |
2021 | 1,328,045 | 2,081,483 |
2020 | 609,341 | 988,625 |
2019 | 295,840 | 543,277 |
2018/Prior | 533,486 | 468,848 |
Prior |  | 299,395 |
Total loans | 8,058,961 | 7,430,603 |
Current-period gross writeoffs |  |  |
Total | $ 10,184 | 9,479 | $ 9,024
Commercial Real Estate: other construction and land development |  |  |
Current-period gross writeoffs |  |  |
Number of loans downgraded | item | 2 |  |
Commercial real estate: farmland & commercial |  |  |
Current-period gross writeoffs |  |  |
Number of loans downgraded | item | 2 |  |
Commercial, financial and agricultural |  |  |
Loan portfolio by credit quality indicator |  |  |
Total loans | $ 4,802,622 | 4,373,373 |
Commercial, financial and agricultural | Domestic | Commercial. |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 811,918 |  |
2022 | 305,621 | 766,789 |
2021 | 364,498 | 525,241 |
2020 | 50,602 | 97,498 |
2019 | 21,468 | 35,917 |
2018/Prior | 74,123 | 43,841 |
Prior |  | 29,468 |
Total loans | 1,628,230 | 1,498,754 |
Current-period gross writeoffs |  |  |
Total | 9,664 | 9,050 | 8,083
Commercial, financial and agricultural | Domestic | Commercial. | Pass |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 791,233 |  |
2022 | 272,919 | 736,462 |
2021 | 364,271 | 524,879 |
2020 | 50,602 | 96,401 |
2019 | 21,468 | 35,917 |
2018/Prior | 74,119 | 43,792 |
Prior |  | 29,464 |
Total loans | 1,574,612 | 1,466,915 |
Commercial, financial and agricultural | Domestic | Commercial. | Special Review |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 7,613 |  |
2022 | 1,800 | 377 |
2021 | 164 | 213 |
Total loans | 9,577 | 590 |
Commercial, financial and agricultural | Domestic | Commercial. | Watch List - Pass |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 11,865 |  |
Total loans | 11,865 |  |
Commercial, financial and agricultural | Domestic | Commercial. | Watch List - Substandard |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 1,180 |  |
2022 | 92 | 161 |
2021 | 28 | 149 |
2020 |  | 143 |
2018/Prior | 4 | 49 |
Total loans | 1,304 | 502 |
Commercial, financial and agricultural | Domestic | Commercial. | Watch List - Doubtful |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 27 |  |
2022 | 30,810 | 29,789 |
2021 | 35 |  |
2020 |  | 954 |
Prior |  | 4 |
Total loans | 30,872 | 30,747 |
Commercial, financial and agricultural | Domestic | Commercial. | Current Period Gross Write-Offs |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 7,053 |  |
2022 | 2,187 |  |
2021 | 155 |  |
2020 | 264 |  |
2019 | 2 |  |
2018/Prior | 3 |  |
Total loans | 9,664 |  |
Commercial, financial and agricultural | Domestic | Commercial Real Estate: other construction and land development | Watch List - Substandard |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 25,230 |  |
Total loans | 25,230 |  |
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 1,040,592 |  |
2022 | 631,029 | 833,401 |
2021 | 419,048 | 584,381 |
2020 | 270,009 | 511,194 |
2019 | 184,248 | 232,633 |
2018/Prior | 248,627 | 325,214 |
Prior |  | 81,295 |
Total loans | 2,793,553 | 2,568,118 |
Current-period gross writeoffs |  |  |
Total |  | 16 | 364
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Pass |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 888,878 |  |
2022 | 628,653 | 811,117 |
2021 | 415,458 | 584,134 |
2020 | 267,705 | 456,200 |
2019 | 184,164 | 232,537 |
2018/Prior | 248,626 | 325,214 |
Prior |  | 81,295 |
Total loans | 2,633,484 | 2,490,497 |
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Special Review |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 5,205 |  |
2022 |  | 2,855 |
2021 | 3,357 |  |
2020 |  | 842 |
Total loans | 8,562 | 3,697 |
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Watch List - Pass |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 16,654 |  |
2022 | 87 | 17,060 |
2021 | 233 | 247 |
Total loans | 16,974 | 17,307 |
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Watch List - Substandard |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 129,644 |  |
2022 | 2,201 | 2,275 |
2020 | 2,304 | 54,152 |
2019 | 84 | 96 |
2018/Prior | 1 |  |
Total loans | 134,234 | 56,523 |
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Watch List - Doubtful |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 211 |  |
2022 | 88 | 94 |
Total loans | 299 | 94 |
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 123,523 |  |
2022 | 94,647 | 127,797 |
2021 | 42,081 | 87,469 |
2020 | 73,652 | 59,035 |
2019 | 10,743 | 12,026 |
2018/Prior | 36,193 | 5,490 |
Prior |  | 14,684 |
Total loans | 380,839 | 306,501 |
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | Pass |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 123,523 |  |
2022 | 94,551 | 127,680 |
2021 | 42,081 | 87,469 |
2020 | 73,652 | 59,035 |
2019 | 10,743 | 12,026 |
2018/Prior | 36,193 | 5,490 |
Prior |  | 14,684 |
Total loans | 380,743 | 306,384 |
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | Watch List - Doubtful |  |  |
Loan portfolio by credit quality indicator |  |  |
2022 | 96 | 117 |
2021 |  |  |
2020 |  |  |
2019 |  |  |
2018/Prior |  |  |
Prior |  |  |
Total loans | 96 | 117 |
Obligations of states and political subdivisions |  |  |
Loan portfolio by credit quality indicator |  |  |
Total loans | 2,091,622 | 1,989,669 |
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 966,695 |  |
2022 | 687,012 | 933,657 |
2021 | 324,238 | 666,754 |
2020 | 96,400 | 173,918 |
2019 | 14,058 | 175,106 |
2018/Prior | 3,219 | 35,069 |
Prior |  | 5,165 |
Total loans | 2,091,622 | 1,989,669 |
Current-period gross writeoffs |  |  |
Total |  | 2 | 2
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | Pass |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 938,739 |  |
2022 | 674,037 | 913,675 |
2021 | 324,238 | 666,347 |
2020 | 96,400 | 173,824 |
2019 | 14,058 | 174,897 |
2018/Prior | 3,219 | 35,069 |
Prior |  | 5,165 |
Total loans | 2,050,691 | 1,968,977 |
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | Special Review |  |  |
Loan portfolio by credit quality indicator |  |  |
2022 |  |  |
2021 |  |  |
2020 |  |  |
2019 |  | 209 |
2018/Prior |  |  |
Prior |  |  |
Total loans |  | 209 |
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | Watch List - Doubtful |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 2,726 |  |
2022 | 12,975 | 19,982 |
2021 |  | 407 |
2020 |  | 94 |
Total loans | 15,701 | 20,483 |
Real estate - mortgage |  |  |
Loan portfolio by credit quality indicator |  |  |
Total loans | 938,901 | 865,994 |
Real estate - mortgage | Domestic | Residential: first lien |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 180,127 |  |
2022 | 83,661 | 138,848 |
2021 | 68,409 | 82,826 |
2020 | 39,935 | 49,591 |
2019 | 27,499 | 40,985 |
2018/Prior | 78,401 | 33,814 |
Prior |  | 79,660 |
Total loans | 478,032 | 425,724 |
Current-period gross writeoffs |  |  |
Total | 43 | 160 | 373
Real estate - mortgage | Domestic | Residential: first lien | Pass |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 180,127 |  |
2022 | 83,568 | 138,771 |
2021 | 68,082 | 82,466 |
2020 | 39,935 | 49,591 |
2019 | 27,499 | 40,985 |
2018/Prior | 78,306 | 33,814 |
Prior |  | 79,660 |
Total loans | 477,517 | 425,287 |
Real estate - mortgage | Domestic | Residential: first lien | Watch List - Substandard |  |  |
Loan portfolio by credit quality indicator |  |  |
2021 | 327 | 360 |
2018/Prior | 95 |  |
Total loans | 422 | 360 |
Real estate - mortgage | Domestic | Residential: first lien | Watch List - Doubtful |  |  |
Loan portfolio by credit quality indicator |  |  |
2022 | 93 | 77 |
Total loans | 93 | 77 |
Real estate - mortgage | Domestic | Residential: first lien | Current Period Gross Write-Offs |  |  |
Loan portfolio by credit quality indicator |  |  |
2018/Prior | 43 |  |
Total loans | 43 |  |
Real estate - mortgage | Domestic | Residential Junior Lien |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 88,628 |  |
2022 | 76,845 | 92,256 |
2021 | 96,411 | 109,127 |
2020 | 76,490 | 91,130 |
2019 | 34,870 | 41,273 |
2018/Prior | 87,625 | 21,975 |
Prior |  | 84,509 |
Total loans | 460,869 | 440,270 |
Current-period gross writeoffs |  |  |
Total | 298 | 28 | 25
Real estate - mortgage | Domestic | Residential Junior Lien | Pass |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 88,628 |  |
2022 | 76,845 | 92,256 |
2021 | 96,411 | 108,815 |
2020 | 76,490 | 91,130 |
2019 | 34,870 | 41,273 |
2018/Prior | 87,625 | 21,975 |
Prior |  | 84,509 |
Total loans | 460,869 | 439,958 |
Real estate - mortgage | Domestic | Residential Junior Lien | Watch List - Doubtful |  |  |
Loan portfolio by credit quality indicator |  |  |
2021 |  | 312 |
Total loans |  | 312 |
Real estate - mortgage | Domestic | Residential Junior Lien | Current Period Gross Write-Offs |  |  |
Loan portfolio by credit quality indicator |  |  |
2018/Prior | 298 |  |
Total loans | 298 |  |
Consumer |  |  |
Loan portfolio by credit quality indicator |  |  |
Total loans | 45,121 | 41,592 |
Consumer | Domestic |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 36,639 |  |
2022 | 5,366 | 31,962 |
2021 | 1,043 | 6,603 |
2020 | 237 | 897 |
2019 | 157 | 489 |
2018/Prior | 1,679 | 28 |
Prior |  | 1,613 |
Total loans | 45,121 | 41,592 |
Current-period gross writeoffs |  |  |
Total | 179 | 223 | 176
Consumer | Domestic | Pass |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 36,639 |  |
2022 | 5,366 | 31,962 |
2021 | 1,043 | 6,603 |
2020 | 237 | 897 |
2019 | 157 | 489 |
2018/Prior | 1,679 | 28 |
Prior |  | 1,613 |
Total loans | 45,121 | 41,592 |
Consumer | Domestic | Current Period Gross Write-Offs |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 54 |  |
2022 | 115 |  |
2021 | 9 |  |
2019 | 1 |  |
Total loans | 179 |  |
Foreign. |  |  |
Loan portfolio by credit quality indicator |  |  |
Total loans | 180,695 | 159,975 |
Foreign. | Foreign |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 116,104 |  |
2022 | 43,842 | 124,265 |
2021 | 12,317 | 19,082 |
2020 | 2,016 | 5,362 |
2019 | 2,797 | 4,848 |
2018/Prior | 3,619 | 3,417 |
Prior |  | 3,001 |
Total loans | 180,695 | 159,975 |
Current-period gross writeoffs |  |  |
Total |  |  | $ 1
Foreign. | Foreign | Pass |  |  |
Loan portfolio by credit quality indicator |  |  |
2023 | 116,104 |  |
2022 | 43,842 | 124,265 |
2021 | 12,317 | 19,082 |
2020 | 2,016 | 5,362 |
2019 | 2,797 | 4,848 |
2018/Prior | 3,619 | 3,417 |
Prior |  | 3,001 |
Total loans | $ 180,695 | $ 159,975 |

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