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Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 30, 2022 | Jun. 30, 2021 | Jun. 30, 2022 | Jun. 30, 2021 | Mar. 31, 2022 | Dec. 31, 2021 | Mar. 31, 2021 | Dec. 31, 2020
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |
Allowance for credit loss | $ 42,452 | $ 46,365 | $ 42,452 | $ 46,365 | $ 40,966 | $ 39,676 | $ 49,828 | $ 52,420
Unfunded Commitments [Member] | Provision for Credit Losses [Member] |  |  |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |
Credit loss (benefit) expense | 119 | $ (765) | 360 | $ (1,040) |  |  |  |
Unfunded Commitments [Member] | Other Liabilities [Member] |  |  |  |  |  |  |  |
Commitments And Contingencies [Line Items] |  |  |  |  |  |  |  |
Allowance for credit loss | $ 2,200 |  | $ 2,200 |  |  | $ 1,800 |  |

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