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Allowance for Credit Losses (Impaired Loans) (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Dec. 31, 2022
--- | --- | ---
Loan loss allowances |  |
Total troubled debt restructuring |  | $ 3,213
Period of charge off for past due unsecured commercial loans | 90 days |
Real estate - mortgage | Domestic | Residential: first lien |  |
Loan loss allowances |  |
Total troubled debt restructuring |  | 1,642
Real estate - mortgage | Domestic | Residential Junior Lien |  |
Loan loss allowances |  |
Total troubled debt restructuring |  | 714
Consumer | Domestic |  |
Loan loss allowances |  |
Total troubled debt restructuring |  | 802
Foreign. | Foreign |  |
Loan loss allowances |  |
Total troubled debt restructuring |  | $ 55

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