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Allowance for Credit Losses (Non-accrual Basis By Loan Class) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Loan loss allowances, financing receivable past due
Non-accrual loans, total	$ 2,232	$ 19,822
Commercial, financial and agricultural | Domestic | Commercial
Loan loss allowances, financing receivable past due
Non-accrual loans, total	567	1,189
Commercial, financial and agricultural | Domestic | Commercial Real Estate: Farmland and Commercial
Loan loss allowances, financing receivable past due
Non-accrual loans, total	404	439
Commercial, financial and agricultural | Domestic | Commercial Real Estate: Multifamily
Loan loss allowances, financing receivable past due
Non-accrual loans, total	121	134
Real estate - construction | Domestic | Commercial Real Estate: other construction and land development
Loan loss allowances, financing receivable past due
Non-accrual loans, total	769	17,496
Real estate - mortgage | Domestic | Residential First Lien
Loan loss allowances, financing receivable past due
Non-accrual loans, total	336	526
Real estate - mortgage | Domestic | Residential Junior Lien
Loan loss allowances, financing receivable past due
Non-accrual loans, total	$ 35	$ 38

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- Definition

Amount of financing receivable on nonaccrual status.

+ 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 http://asc.fasb.org/extlink&oid=121611835&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 http://asc.fasb.org/extlink&oid=121599337&loc=SL82919258-210447

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+ References

No definition available.

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