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Allowance for Credit Losses (Aging By Loan Class) (Details) - USD ($) | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | ---
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | $ 8,238,000 | $ 59,705,000 | $ 40,674,000
Past due | 38,258,000 | 84,450,000 |
Loans, current | 7,503,496,000 | 6,810,496,000 |
Total loans | 7,541,754,000 | 6,894,946,000 |
30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 9,307,000 | 18,169,000 |
60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 3,606,000 | 4,937,000 |
90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 25,345,000 | 61,344,000 |
Domestic | Commercial Loan [Member] |  |  |
Financing receivable recorded investment |  |  |
Total loans | 1,785,936,000 |  |
Domestic | Commercial Real Estate: other construction and land development |  |  |
Financing receivable recorded investment |  |  |
Total loans | 1,846,757,000 |  |
Domestic | Commercial Real Estate Farmland and Commercial Receivable [Member] |  |  |
Financing receivable recorded investment |  |  |
Total loans | 2,289,308,000 |  |
Domestic | Commercial Real Estate Multifamily Receivable [Member] |  |  |
Financing receivable recorded investment |  |  |
Total loans | 441,044,000 |  |
Domestic | Residential First Mortgage Financing Receivable [Member] |  |  |
Financing receivable recorded investment |  |  |
Total loans | 405,119,000 |  |
Domestic | Residential Junior Lien |  |  |
Financing receivable recorded investment |  |  |
Total loans | 594,025,000 |  |
Commercial, financial and agricultural |  |  |
Financing receivable recorded investment |  |  |
Total loans | 4,516,288,000 | 3,379,837,000 |
Commercial, financial and agricultural | Domestic | Commercial Loan [Member] |  |  |
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | 318,000 | 421,000 |
Past due | 3,603,000 | 5,052,000 |
Loans, current | 1,782,333,000 | 1,287,608,000 |
Total loans | 1,785,936,000 | 1,292,660,000 |
Commercial, financial and agricultural | Domestic | Commercial Loan [Member] | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 1,931,000 | 3,134,000 |
Commercial, financial and agricultural | Domestic | Commercial Loan [Member] | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 1,109,000 | 626,000 |
Commercial, financial and agricultural | Domestic | Commercial Loan [Member] | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 563,000 | 1,292,000 |
Commercial, financial and agricultural | Domestic | Commercial Real Estate Farmland and Commercial Receivable [Member] |  |  |
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | 186,000 | 54,878,000 |
Past due | 2,840,000 | 65,017,000 |
Loans, current | 2,286,468,000 | 1,831,730,000 |
Total loans | 2,289,308,000 | 1,896,747,000 |
Commercial, financial and agricultural | Domestic | Commercial Real Estate Farmland and Commercial Receivable [Member] | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 2,435,000 | 8,058,000 |
Commercial, financial and agricultural | Domestic | Commercial Real Estate Farmland and Commercial Receivable [Member] | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 219,000 | 2,031,000 |
Commercial, financial and agricultural | Domestic | Commercial Real Estate Farmland and Commercial Receivable [Member] | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 186,000 | 54,928,000 |
Commercial, financial and agricultural | Domestic | Commercial Real Estate Multifamily Receivable [Member] |  |  |
Financing receivable recorded investment |  |  |
Past due | 126,000 | 478,000 |
Loans, current | 440,918,000 | 189,952,000 |
Total loans | 441,044,000 | 190,430,000 |
Commercial, financial and agricultural | Domestic | Commercial Real Estate Multifamily Receivable [Member] | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 126,000 | 313,000 |
Commercial, financial and agricultural | Domestic | Commercial Real Estate Multifamily Receivable [Member] | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due |  | 165,000 |
Commercial Real Estate Portfolio Segment [Member] |  |  |
Financing receivable recorded investment |  |  |
Total loans | 1,846,757,000 | 2,185,883,000 |
Commercial Real Estate Portfolio Segment [Member] | Domestic | Commercial Real Estate: other construction and land development |  |  |
Financing receivable recorded investment |  |  |
Past due | 18,500,000 | 564,000 |
Loans, current | 1,828,257,000 | 2,185,319,000 |
Total loans | 1,846,757,000 | 2,185,883,000 |
Commercial Real Estate Portfolio Segment [Member] | Domestic | Commercial Real Estate: other construction and land development | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 1,059,000 | 509,000 |
Commercial Real Estate Portfolio Segment [Member] | Domestic | Commercial Real Estate: other construction and land development | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 854,000 | 55,000 |
Commercial Real Estate Portfolio Segment [Member] | Domestic | Commercial Real Estate: other construction and land development | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 16,587,000 |  |
Real estate - mortgage |  |  |
Financing receivable recorded investment |  |  |
Total loans | 999,144,000 | 1,140,377,000 |
Real estate - mortgage | Domestic | Residential First Mortgage Financing Receivable [Member] |  |  |
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | 5,890,000 | 3,107,000 |
Past due | 9,490,000 | 8,559,000 |
Loans, current | 395,629,000 | 425,342,000 |
Total loans | 405,119,000 | 433,901,000 |
Real estate - mortgage | Domestic | Residential First Mortgage Financing Receivable [Member] | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 2,399,000 | 3,229,000 |
Real estate - mortgage | Domestic | Residential First Mortgage Financing Receivable [Member] | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 926,000 | 1,670,000 |
Real estate - mortgage | Domestic | Residential First Mortgage Financing Receivable [Member] | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 6,165,000 | 3,660,000 |
Real estate - mortgage | Domestic | Residential Junior Lien |  |  |
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | 1,197,000 | 1,200,000 |
Past due | 2,005,000 | 2,789,000 |
Loans, current | 592,020,000 | 703,687,000 |
Total loans | 594,025,000 | 706,476,000 |
Real estate - mortgage | Domestic | Residential Junior Lien | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 561,000 | 1,112,000 |
Real estate - mortgage | Domestic | Residential Junior Lien | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 247,000 | 477,000 |
Real estate - mortgage | Domestic | Residential Junior Lien | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 1,197,000 | 1,200,000 |
Consumer |  |  |
Financing receivable recorded investment |  |  |
Total loans | 40,595,000 | 47,800,000 |
Consumer | Domestic |  |  |
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | 79,000 | 88,000 |
Past due | 468,000 | 630,000 |
Loans, current | 40,127,000 | 47,170,000 |
Total loans | 40,595,000 | 47,800,000 |
Consumer | Domestic | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 318,000 | 467,000 |
Consumer | Domestic | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 71,000 | 75,000 |
Consumer | Domestic | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 79,000 | 88,000 |
Foreign |  |  |
Financing receivable recorded investment |  |  |
Total loans | 138,970,000 | 141,049,000 |
Foreign | Foreign |  |  |
Financing receivable recorded investment |  |  |
Past due 90 days or Greater and Still Accruing | 568,000 | 11,000 |
Past due | 1,226,000 | 1,361,000 |
Loans, current | 137,744,000 | 139,688,000 |
Total loans | 138,970,000 | 141,049,000 |
Foreign | Foreign | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 478,000 | 1,347,000 |
Foreign | Foreign | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 180,000 | 3,000 |
Foreign | Foreign | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | $ 568,000 | $ 11,000 |

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