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Loans (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
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Summary of loans, by loan type |  |
Total loans | $ 7,541,754 | $ 6,894,946
Commercial, financial and agricultural |  |
Summary of loans, by loan type |  |
Total loans | 4,516,288 | 3,379,837
Real estate - mortgage |  |
Summary of loans, by loan type |  |
Total loans | 999,144 | 1,140,377
Commercial Real Estate Portfolio Segment [Member] |  |
Summary of loans, by loan type |  |
Total loans | 1,846,757 | 2,185,883
Consumer |  |
Summary of loans, by loan type |  |
Total loans | 40,595 | 47,800
Foreign |  |
Summary of loans, by loan type |  |
Total loans | $ 138,970 | $ 141,049

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