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Allowance for Credit Losses (Non-accrual Basis By Loan Class) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Loan loss allowances, financing receivable past due |  |  |
Non-accrual loans, total | $ 1,921,000 | $ 19,822,000 | $ 4,886,000
Reduced interest income on non-accrual loans | 169,000 | 694,000 | $ 340,000
Commercial, financial and agricultural | Domestic | Commercial. |  |  |
Loan loss allowances, financing receivable past due |  |  |
Non-accrual loans, total | 298,000 | 1,189,000 |
Commercial, financial and agricultural | Domestic | Commercial real estate: farmland & commercial |  |  |
Loan loss allowances, financing receivable past due |  |  |
Non-accrual loans, total | 562,000 | 439,000 |
Commercial, financial and agricultural | Domestic | Commercial real estate: multifamily |  |  |
Loan loss allowances, financing receivable past due |  |  |
Non-accrual loans, total | 131,000 | 134,000 |
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 | 589,000 | 17,496,000 |
Real estate - mortgage | Domestic | Residential: first lien |  |  |
Loan loss allowances, financing receivable past due |  |  |
Non-accrual loans, total | $ 341,000 | 526,000 |
Real estate - mortgage | Domestic | Residential Junior Lien |  |  |
Loan loss allowances, financing receivable past due |  |  |
Non-accrual loans, total |  | $ 38,000 |

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