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Loans (Details) - USD ($) $ in Thousands | Sep. 30, 2021 | Dec. 31, 2020
--- | --- | ---
Summary of loans, by loan type |  |
Total loans | $ 7,404,158 | $ 7,541,754
Commercial, financial and agricultural |  |
Summary of loans, by loan type |  |
Total loans | 4,680,091 | 4,516,288
Real estate - mortgage |  |
Summary of loans, by loan type |  |
Total loans | 876,313 | 999,144
Commercial Real Estate Portfolio Segment [Member] |  |
Summary of loans, by loan type |  |
Total loans | 1,671,212 | 1,846,757
Consumer |  |
Summary of loans, by loan type |  |
Total loans | 40,699 | 40,595
Foreign. |  |
Summary of loans, by loan type |  |
Total loans | $ 135,843 | $ 138,970

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