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Allowance for Credit Losses (Non-accrual Basis By Loan Class) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Loan loss allowances, financing receivable past due
Non-accrual loans, total	$ 51,648,000	$ 1,921,000	$ 19,822,000
Reduced interest income on non-accrual loans	116,000	169,000	$ 694,000
Commercial, financial and agricultural | Domestic | Commercial.
Loan loss allowances, financing receivable past due
Non-accrual loans, total	30,747,000	298,000
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial
Loan loss allowances, financing receivable past due
Non-accrual loans, total	94,000	562,000
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily
Loan loss allowances, financing receivable past due
Non-accrual loans, total	117,000	131,000
Obligations of states and political subdivisions | Domestic | Commercial Real Estate: other construction and land development
Loan loss allowances, financing receivable past due
Non-accrual loans, total	20,483,000	589,000
Real estate - mortgage | Domestic | Residential: first lien
Loan loss allowances, financing receivable past due
Non-accrual loans, total	$ 207,000	$ 341,000

X

- Definition

Represents the reduction in interest income on recorded investment in financing receivables that are on nonaccrual status.

+ References

No definition available.

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- Definition

Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5111-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (3)

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (2)

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- Definition

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