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Allowance for Credit Losses (Aging By Loan Class) (Details) - USD ($) | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | --- | ---
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | $ 8,642,000 | $ 8,238,000 | $ 59,705,000
Loans | 7,209,151,000 | 7,541,754,000 |
Current |  |  |
Financing receivable recorded investment |  |  |
Loans | 7,171,688,000 | 7,503,496,000 |
Total Past Due |  |  |
Financing receivable recorded investment |  |  |
Loans | 37,463,000 | 38,258,000 |
30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 25,836,000 | 9,307,000 |
60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 2,456,000 | 3,606,000 |
90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Loans | 9,171,000 | 25,345,000 |
Commercial, financial and agricultural |  |  |
Financing receivable recorded investment |  |  |
Loans | 4,497,444,000 | 4,516,288,000 |
Commercial, financial and agricultural | Domestic | Commercial. |  |  |
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | 577,000 | 318,000 |
Loans | 1,501,852,000 | 1,785,936,000 |
Commercial, financial and agricultural | Domestic | Commercial. | Current |  |  |
Financing receivable recorded investment |  |  |
Loans | 1,498,438,000 | 1,782,333,000 |
Commercial, financial and agricultural | Domestic | Commercial. | Total Past Due |  |  |
Financing receivable recorded investment |  |  |
Loans | 3,414,000 | 3,603,000 |
Commercial, financial and agricultural | Domestic | Commercial. | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 2,534,000 | 1,931,000 |
Commercial, financial and agricultural | Domestic | Commercial. | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 303,000 | 1,109,000 |
Commercial, financial and agricultural | Domestic | Commercial. | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Loans | 577,000 | 563,000 |
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial |  |  |
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | 307,000 | 186,000 |
Loans | 2,711,056,000 | 2,289,308,000 |
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Current |  |  |
Financing receivable recorded investment |  |  |
Loans | 2,692,076,000 | 2,286,468,000 |
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | Total Past Due |  |  |
Financing receivable recorded investment |  |  |
Loans | 18,980,000 | 2,840,000 |
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 18,164,000 | 2,435,000 |
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 172,000 | 219,000 |
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Loans | 644,000 | 186,000 |
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily |  |  |
Financing receivable recorded investment |  |  |
Loans | 284,536,000 | 441,044,000 |
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | Current |  |  |
Financing receivable recorded investment |  |  |
Loans | 284,536,000 | 440,918,000 |
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | Total Past Due |  |  |
Financing receivable recorded investment |  |  |
Loans |  | 126,000 |
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Loans |  | 126,000 |
Obligations of states and political subdivisions |  |  |
Financing receivable recorded investment |  |  |
Loans | 1,668,113,000 | 1,846,757,000 |
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development |  |  |
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | 188,000 |  |
Loans | 1,668,113,000 | 1,846,757,000 |
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | Current |  |  |
Financing receivable recorded investment |  |  |
Loans | 1,667,092,000 | 1,828,257,000 |
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | Total Past Due |  |  |
Financing receivable recorded investment |  |  |
Loans | 1,021,000 | 18,500,000 |
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 499,000 | 1,059,000 |
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 334,000 | 854,000 |
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Loans | 188,000 | 16,587,000 |
Real estate - mortgage |  |  |
Financing receivable recorded investment |  |  |
Loans | 867,831,000 | 999,144,000 |
Real estate - mortgage | Domestic | Residential: first lien |  |  |
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | 4,937,000 | 5,890,000 |
Loans | 403,658,000 | 405,119,000 |
Real estate - mortgage | Domestic | Residential: first lien | Current |  |  |
Financing receivable recorded investment |  |  |
Loans | 394,975,000 | 395,629,000 |
Real estate - mortgage | Domestic | Residential: first lien | Total Past Due |  |  |
Financing receivable recorded investment |  |  |
Loans | 8,683,000 | 9,490,000 |
Real estate - mortgage | Domestic | Residential: first lien | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 2,342,000 | 2,399,000 |
Real estate - mortgage | Domestic | Residential: first lien | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 1,212,000 | 926,000 |
Real estate - mortgage | Domestic | Residential: first lien | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Loans | 5,129,000 | 6,165,000 |
Real estate - mortgage | Domestic | Residential Junior Lien |  |  |
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | 1,055,000 | 1,197,000 |
Loans | 464,173,000 | 594,025,000 |
Real estate - mortgage | Domestic | Residential Junior Lien | Current |  |  |
Financing receivable recorded investment |  |  |
Loans | 462,256,000 | 592,020,000 |
Real estate - mortgage | Domestic | Residential Junior Lien | Total Past Due |  |  |
Financing receivable recorded investment |  |  |
Loans | 1,917,000 | 2,005,000 |
Real estate - mortgage | Domestic | Residential Junior Lien | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 747,000 | 561,000 |
Real estate - mortgage | Domestic | Residential Junior Lien | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 115,000 | 247,000 |
Real estate - mortgage | Domestic | Residential Junior Lien | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Loans | 1,055,000 | 1,197,000 |
Consumer |  |  |
Financing receivable recorded investment |  |  |
Loans | 40,966,000 | 40,595,000 |
Consumer | Domestic |  |  |
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | 4,000 | 79,000 |
Loans | 40,966,000 | 40,595,000 |
Consumer | Domestic | Current |  |  |
Financing receivable recorded investment |  |  |
Loans | 40,643,000 | 40,127,000 |
Consumer | Domestic | Total Past Due |  |  |
Financing receivable recorded investment |  |  |
Loans | 323,000 | 468,000 |
Consumer | Domestic | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 231,000 | 318,000 |
Consumer | Domestic | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 88,000 | 71,000 |
Consumer | Domestic | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Loans | 4,000 | 79,000 |
Foreign. |  |  |
Financing receivable recorded investment |  |  |
Loans | 134,797,000 | 138,970,000 |
Foreign. | Foreign |  |  |
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | 1,574,000 | 568,000 |
Loans | 134,797,000 | 138,970,000 |
Foreign. | Foreign | Current |  |  |
Financing receivable recorded investment |  |  |
Loans | 131,672,000 | 137,744,000 |
Foreign. | Foreign | Total Past Due |  |  |
Financing receivable recorded investment |  |  |
Loans | 3,125,000 | 1,226,000 |
Foreign. | Foreign | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 1,319,000 | 478,000 |
Foreign. | Foreign | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Loans | 232,000 | 180,000 |
Foreign. | Foreign | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Loans | $ 1,574,000 | $ 568,000 |

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