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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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