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Retirement Benefit Plans - Schedule of Fair Value of Plan Assets (Details) - USD ($) $ in Thousands | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | $ 23,671 | $ 22,370
Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 2,074 | 7,747
Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 21,597 | 14,623
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 | 637 | 1,450
Mid Cap | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 637 | 1,450
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
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
Large Cap | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets |  | 0
Large Cap | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets |  | 0
International |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 940 | 2,660
International | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 940 | 2,660
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 CIT I |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 7,782 | 3,106
Wells Fargo Liability Driven Solution CIT I | 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 CIT I | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 7,782 | 3,106
Wells Fargo Liability Driven Solution CIT I | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 | 0
Wells Fargo Liability Driven Solution CIT II |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 7,026 |
Wells Fargo Liability Driven Solution CIT II | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 |
Wells Fargo Liability Driven Solution CIT II | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 7,026 |
Wells Fargo Liability Driven Solution CIT II | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 0 |
Wells Fargo BlackRock International Equity |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 616 | 959
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 | 616 | 959
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
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
Wells Fargo Core Bond | Significant Other Observable Inputs (Level 2) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets |  | 1,552
Wells Fargo Core Bond | Significant Unobservable Inputs (Level 3) |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets |  | 0
Wells Fargo/Causeway International Value |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Fair value of plan assets | 586 | 923
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 | 586 | 923
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 | 950 | 1,268
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 | 950 | 1,268
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 | 968 | 1,240
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 | 968 | 1,240
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 | 1,015 | 1,544
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 | 1,015 | 1,544
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 | 332 | 702
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 | 332 | 702
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 | 419 | 781
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 | 419 | 781
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 | 469 | 627
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 | 469 | 627
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 | 465 | 639
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 | 465 | 639
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 | 487 | 643
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 | 487 | 643
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 | 482 | 639
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 | 482 | 639
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 | 497 | 404
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 | 497 | 404
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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