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Retirement Benefit Plans (Schedule of Fair Value of Plan Assets) (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 22,370 | $ 20,605
Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 7,747 | 7,060
Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 14,623 | 13,545
Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Mid Cap |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 1,450 | 2,239
Mid Cap | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 1,450 | 2,239
Mid Cap | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Mid Cap | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Large Cap |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 3,233 | 2,574
Large Cap | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 3,233 | 2,574
Large Cap | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Large Cap | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
International |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 2,660 | 1,879
International | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 2,660 | 1,879
International | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
International | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo Liability Driven Solution |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 3,106 | 2,866
Wells Fargo Liability Driven Solution | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo Liability Driven Solution | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 3,106 | 2,866
Wells Fargo Liability Driven Solution | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo BlackRock International Equity |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 959 | 861
Wells Fargo BlackRock International Equity | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo BlackRock International Equity | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 959 | 861
Wells Fargo BlackRock International Equity | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo Core Bond |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 1,552 | 1,413
Wells Fargo Core Bond | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo Core Bond | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 1,552 | 1,413
Wells Fargo Core Bond | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo/Causeway International Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 923 | 864
Wells Fargo/Causeway International Value | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo/Causeway International Value | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 923 | 864
Wells Fargo/Causeway International Value | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo BlackRock Large Cap Growth Index Fund |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 1,268 | 1,153
Wells Fargo BlackRock Large Cap Growth Index Fund | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo BlackRock Large Cap Growth Index Fund | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 1,268 | 1,153
Wells Fargo BlackRock Large Cap Growth Index Fund | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo BlackRock Large Cap Value Index Fund |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 1,240 | 1,159
Wells Fargo BlackRock Large Cap Value Index Fund | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo BlackRock Large Cap Value Index Fund | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 1,240 | 1,159
Wells Fargo BlackRock Large Cap Value Index Fund | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo Multi-Manager Small Cap |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 1,544 | 1,434
Wells Fargo Multi-Manager Small Cap | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo Multi-Manager Small Cap | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 1,544 | 1,434
Wells Fargo Multi-Manager Small Cap | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo BlackRock Russell 2000 Index Fund |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 702 | 667
Wells Fargo BlackRock Russell 2000 Index Fund | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo BlackRock Russell 2000 Index Fund | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 702 | 667
Wells Fargo BlackRock Russell 2000 Index Fund | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo BlackRock S&P Mid Cap Index Fund |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 781 | 732
Wells Fargo BlackRock S&P Mid Cap Index Fund | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo BlackRock S&P Mid Cap Index Fund | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 781 | 732
Wells Fargo BlackRock S&P Mid Cap Index Fund | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo/MFS Value CIT F |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 627 | 599
Wells Fargo/MFS Value CIT F | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo/MFS Value CIT F | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 627 | 599
Wells Fargo/MFS Value CIT F | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo/T. Rowe Price Large-Cap Growth Managed CIT |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 639 | 602
Wells Fargo/T. Rowe Price Large-Cap Growth Managed CIT | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo/T. Rowe Price Large-Cap Growth Managed CIT | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 639 | 602
Wells Fargo/T. Rowe Price Large-Cap Growth Managed CIT | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo/T. Rowe Price Equity Income Managed CIT |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 643 | 590
Wells Fargo/T. Rowe Price Equity Income Managed CIT | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo/T. Rowe Price Equity Income Managed CIT | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 643 | 590
Wells Fargo/T. Rowe Price Equity Income Managed CIT | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo Voya Large Cap Growth CIT F |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 639 | 605
Wells Fargo Voya Large Cap Growth CIT F | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo Voya Large Cap Growth CIT F | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 639 | 605
Wells Fargo Voya Large Cap Growth CIT F | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Cash & Short-term Investments |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 404 | 368
Cash & Short-term Investments | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 404 | 368
Cash & Short-term Investments | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Cash & Short-term Investments | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 0 | $ 0

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