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Employee Benefits (Various Benefits - Narrative) (Details) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($) fund | Dec. 31, 2018 USD ($) fund
Schedule Of Employee Benefits [Line Items] |  |  |
Percentage of internal revenue contribution |  | 25.00% |
Percentage of internal revenue service limitations |  | 6.00% |
Number of investment funds | fund |  | 11 |
Number of equity funds | fund |  | 7 | 6
Number of bond funds | fund |  | 3 | 3
Number of real estate funds | fund |  | 1 | 1
Cash surrender value of life insurance |  | $ 18,457 | $ 18,018
Increase in cash surrender value of insurance |  | 398 | 401
Accrued expenses and other liabilities |  | 11,156 | 10,108
Noninterest expense |  | 27,925 | 26,120
Employer contribution in defined contribution plan |  | 828 | 782
Scenario, Plan [Member] |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |
Estimated net actuarial loss | $ 285 |  |
Postretirement Life Insurance [Member] |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |
Liability related to these postretirement benefits |  | 1,330 | 1,276
Postemployment benefit expense |  | 54 | 16
Postemployment Retirement Benefits [Member] |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |
Noninterest expense |  | 78 | 94
Liability related to these postretirement benefits |  | 2,123 | 2,108
Officer [Member] | Deferred Compensation, Share-based Payments [Member] |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |
Accrued expenses and other liabilities |  | 1,163 | 975
Noninterest expense |  | 593 | 586
Deferred Compensation Arrangement with Individual, by Type of Compensation, Pension and Other Postretirement Benefits [Member] | Director [Member] |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |
Accrued expenses and other liabilities |  | 2,086 | 1,687
Noninterest expense |  | $ 126 | $ 129
Maximum | Postemployment Retirement Benefits [Member] |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |
Post retirement benefit period |  | 20 years |
Maximum | Officer [Member] | Deferred Compensation, Share-based Payments [Member] |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |
Terms of services |  | 5 years |
Minimum | Postemployment Retirement Benefits [Member] |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |
Post retirement benefit period |  | 15 years |
Minimum | Officer [Member] | Deferred Compensation, Share-based Payments [Member] |  |  |
Schedule Of Employee Benefits [Line Items] |  |  |
Terms of services |  | 1 year |

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