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Employee Benefits (Schedule of fair value of pension plan assets, by fair value hierarchy) (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets at fair value | $ 22,839 | $ 22,634 | $ 20,628
Defined Benefit Pension Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets at fair value | 22,839 | 22,634 |
Defined Benefit Pension Plan | Investment in separate accounts fixed income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets at fair value | 15,689 | 15,189 |
Defined Benefit Pension Plan | Investment in separate accounts equity |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets at fair value | 7,150 | 6,206 |
Defined Benefit Pension Plan | Investment in separate accounts other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets at fair value |  | 1,239 |
Quoted Prices Active Markets for Identical Assets (Level 1) | Defined Benefit Pension Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets at fair value | 22,839 | 22,634 |
Quoted Prices Active Markets for Identical Assets (Level 1) | Defined Benefit Pension Plan | Investment in separate accounts fixed income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets at fair value | 15,689 | 15,189 |
Quoted Prices Active Markets for Identical Assets (Level 1) | Defined Benefit Pension Plan | Investment in separate accounts equity |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets at fair value | $ 7,150 | 6,206 |
Quoted Prices Active Markets for Identical Assets (Level 1) | Defined Benefit Pension Plan | Investment in separate accounts other |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Plan assets at fair value |  | $ 1,239 |

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