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Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Summary of loans, by loan type
Total loans	$ 7,896,899	$ 7,430,603
Commercial, financial and agricultural
Summary of loans, by loan type
Total loans	4,637,170	4,373,373
Real estate - mortgage
Summary of loans, by loan type
Total loans	907,615	865,994
Obligations of states and political subdivisions
Summary of loans, by loan type
Total loans	2,126,302	1,989,669
Consumer
Summary of loans, by loan type
Total loans	44,767	41,592
Foreign.
Summary of loans, by loan type
Total loans	$ 181,045	$ 159,975

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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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-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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-Paragraph 5
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-Publisher FASB
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