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Restructuring Charges (Narrative) (Details) $ in Thousands |  | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jul. 17, 2020 Branch | Oct. 31, 2020 Branch | Sep. 30, 2023 USD ($) | Sep. 30, 2022 USD ($) | Sep. 30, 2023 USD ($) | Sep. 30, 2022 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Restructuring Cost And Reserve [Line Items] |  |  |  |  |  |  |  |  |
Number of bank branch closure | Branch | 6 |  |  |  |  |  |  |  |
Percentage of branch network | 10.00% |  |  |  |  |  |  |  |
Percentage of branch network impact | 6.00% |  |  |  |  |  |  |  |
Number of additional branches planned to close | Branch |  | 1 |  |  |  |  |  |  |
Pre tax expense related branch closures |  |  |  |  |  |  |  |  | $ 1,700
Restructuring charges |  |  | $ (55) | $ 0 | $ (74) | $ 1,269 | $ 1,600 | $ 111 |
Restructuring recoveries |  |  | $ 55 |  | 74 |  |  |  |
Long lived assets held for sale |  |  |  |  | $ 1,300 |  | $ 1,500 |  |
Employee Severance [Member] |  |  |  |  |  |  |  |  |
Restructuring Cost And Reserve [Line Items] |  |  |  |  |  |  |  |  |
Pre tax expense related branch closures |  |  |  |  |  |  |  |  | 200
Lease Termination Costs [Member] |  |  |  |  |  |  |  |  |
Restructuring Cost And Reserve [Line Items] |  |  |  |  |  |  |  |  |
Pre tax expense related branch closures |  |  |  |  |  |  |  |  | 500
Valuation Adjustments On Branch Facilities [Member] |  |  |  |  |  |  |  |  |
Restructuring Cost And Reserve [Line Items] |  |  |  |  |  |  |  |  |
Pre tax expense related branch closures |  |  |  |  |  |  |  |  | $ 1,000

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