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Postretirement Benefit Plans - Narrative (Details) - USD ($) $ in Thousands |  | 12 Months Ended |
--- | --- | --- | ---
Jan. 01, 2008 | Dec. 31, 2023 | Dec. 31, 2022 | Oct. 01, 2023
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Immediate Recognition of Actuarial Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Other |  |
Defined Benefit Plan, Net Periodic Benefit (Cost) Credit, Settlement Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] |  | Other | Other |
Postretirement Life Insurance |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined benefit plan, minimum service period requirement | 10 years | 20 years |  |
Life insurance coverage amount until age 65 |  | $ 50 |  |
Decrease in coverage amount after age 65 |  | 5 |  |
Life insurance coverage amount |  | $ 5 |  |
Defined Benefit Postretirement Health and Life Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined benefit plan, minimum service period requirement | 10 years | 20 years |  |
Defined benefit plan, coverage period |  | 5 years |  |
Percentage increase in postretirement benefit health insurance reimbursable premium |  | 36.79% |  |
Defined Benefit Postretirement Health and Life Benefit Plan | Maximum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Postretirement benefit health insurance reimbursable premium |  | $ 5 |  |
Post-Retirement Health Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined benefit plan, minimum service period requirement |  | 20 years |  |
Defined benefit plan, coverage period |  | 5 years |  |
Post-Retirement Health Benefit Plan | Maximum |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Postretirement benefit health insurance reimbursable premium |  | $ 5 |  |
Defined Benefit Postretirement Health And Life Coverage |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined benefit plan, accumulated benefit obligation |  | 271 | $ 297 |
Director's Retirement Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined benefit plan, accumulated benefit obligation |  | 1,300 | 1,300 | $ 1,300
Cash surrender value of bank owned life insurance |  | 4,200 | 4,100 |
Scottdale Defined Benefit Pension Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined benefit plan, accumulated benefit obligation |  | 2,700 | 3,800 |
Settlement gains recognized |  | (4) | 0 |
Scottdale Defined Benefit Pension Plan | Scottdale Bank and Trust Company |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Settlement gains recognized |  | $ 322 | 0 |
Scottdale Defined Benefit Pension Plan | Minimum | Scottdale Bank and Trust Company | Fixed Income Securities |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of target portfolio allocation |  | 30.00% |  |
Scottdale Defined Benefit Pension Plan | Minimum | Scottdale Bank and Trust Company | Equity Securities |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of target portfolio allocation |  | 40.00% |  |
Scottdale Defined Benefit Pension Plan | Maximum | Scottdale Bank and Trust Company | Cash |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of target portfolio allocation |  | 20.00% |  |
Scottdale Defined Benefit Pension Plan | Maximum | Scottdale Bank and Trust Company | Fixed Income Securities |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of target portfolio allocation |  | 50.00% |  |
Scottdale Defined Benefit Pension Plan | Maximum | Scottdale Bank and Trust Company | Equity Securities |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Percentage of target portfolio allocation |  | 60.00% |  |
Riverview Defined Benefit Plan |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Defined benefit plan, accumulated benefit obligation |  | $ 6,400 | $ 6,400 |

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