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Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Thousands | Sep. 30, 2023 | Jun. 30, 2023 | Dec. 31, 2022 | Sep. 30, 2022 | Jun. 30, 2022 | Dec. 31, 2021
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Commitments And Contingencies [Line Items] |  |  |  |  |  |
Allowance for credit loss | $ 49,630 | $ 49,836 | $ 45,413 | $ 44,106 | $ 42,452 | $ 39,676
Unfunded Commitments [Member] | Other Liabilities [Member] |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |
Allowance for credit loss | $ 4,000 |  | $ 4,100 |  |  |

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