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Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Summary of loans, by loan type
Total loans	$ 7,387,537	$ 7,541,754
Commercial, financial and agricultural
Summary of loans, by loan type
Total loans	4,671,168	4,516,288
Real estate - mortgage
Summary of loans, by loan type
Total loans	916,153	999,144
Real estate - construction
Summary of loans, by loan type
Total loans	1,618,493	1,846,757
Consumer
Summary of loans, by loan type
Total loans	40,505	40,595
Foreign
Summary of loans, by loan type
Total loans	$ 141,218	$ 138,970

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