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Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Summary of loans, by loan type
Total loans	$ 8,112,481	$ 8,058,961
Commercial, financial and agricultural
Summary of loans, by loan type
Total loans	4,715,769	4,802,622
Real estate - mortgage
Summary of loans, by loan type
Total loans	954,469	938,901
Obligations of states and political subdivisions
Summary of loans, by loan type
Total loans	2,219,432	2,091,622
Consumer
Summary of loans, by loan type
Total loans	46,358	45,121
Foreign.
Summary of loans, by loan type
Total loans	$ 176,453	$ 180,695

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Section 50
-Paragraph 5
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

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