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Pension Benefits Fair Value of Plan Assets in Heirarchy (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 100.00% |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 100.00% | 100.00% |
Defined Benefit Plan, Plan Assets, Amount | $ 35,941,000 | $ 32,894,000 | $ 35,634,000
Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 27,296,000 | 23,676,000 |
Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 2,450,000 | 3,482,000 |
Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 6,195,000 | 5,736,000 | 5,748,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases | 250,000 | 0 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Realized Gain on Assets | 132,000 | 526,000 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Unrealized Gain on Assets | 298,000 | 41,000 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Disposition | $ (221,000) | $ (579,000) |
Defined Benefit Plan, Equity Securities, US |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 19.10% | 18.70% |
Defined Benefit Plan, Plan Assets, Amount | $ 6,860,000 | $ 6,149,000 |
Defined Benefit Plan, Equity Securities, US | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 4,909,000 | 4,165,000 |
Defined Benefit Plan, Equity Securities, US | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 1,951,000 | 1,984,000 |
Defined Benefit Plan, Equity Securities, US | Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | $ 0 | $ 0 |
Defined Benefit Plan, Equity Securities, Non-US |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 19.90% | 18.30% |
Defined Benefit Plan, Plan Assets, Amount | $ 7,138,000 | $ 6,010,000 |
Defined Benefit Plan, Equity Securities, Non-US | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 7,138,000 | 6,010,000 |
Defined Benefit Plan, Equity Securities, Non-US | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 |
Defined Benefit Plan, Equity Securities, Non-US | Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | $ 0 | $ 0 |
Defined Benefit Plan, Equity Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 37.00% |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 39.00% | 37.00% |
Defined Benefit Plan, Plan Assets, Amount | $ 13,998,000 | $ 12,159,000 |
Defined Benefit Plan, Equity Securities | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 12,047,000 | 10,175,000 |
Defined Benefit Plan, Equity Securities | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 1,951,000 | 1,984,000 |
Defined Benefit Plan, Equity Securities | Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | $ 0 | $ 0 |
Core fixed income |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 18.80% | 16.60% |
Defined Benefit Plan, Plan Assets, Amount | $ 6,770,000 | $ 5,447,000 |
Core fixed income | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 6,770,000 | 5,447,000 |
Core fixed income | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 |
Core fixed income | Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | $ 0 | $ 0 |
Corporate Debt Securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 9.10% | 8.30% |
Defined Benefit Plan, Plan Assets, Amount | $ 3,272,000 | $ 2,755,000 |
Corporate Debt Securities | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 3,272,000 | 2,755,000 |
Corporate Debt Securities | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 |
Corporate Debt Securities | Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | $ 0 | $ 0 |
Total fixed income securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 38.00% |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 27.90% | 24.90% |
Defined Benefit Plan, Plan Assets, Amount | $ 10,042,000 | $ 8,202,000 |
Total fixed income securities | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 10,042,000 | 8,202,000 |
Total fixed income securities | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 |
Total fixed income securities | Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | $ 0 | $ 0 |
Defined Benefit Plan, Real Estate |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 5.10% | 5.70% |
Defined Benefit Plan, Plan Assets, Amount | $ 1,833,000 | $ 1,870,000 |
Defined Benefit Plan, Real Estate | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 |
Defined Benefit Plan, Real Estate | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 |
Defined Benefit Plan, Real Estate | Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | $ 1,833,000 | $ 1,870,000 |
Defined Benefit Plan, Common Collective Trust |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 1.40% | 4.60% |
Defined Benefit Plan, Plan Assets, Amount | $ 499,000 | $ 1,498,000 |
Defined Benefit Plan, Common Collective Trust | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 |
Defined Benefit Plan, Common Collective Trust | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 499,000 | 1,498,000 |
Defined Benefit Plan, Common Collective Trust | Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | $ 0 | $ 0 |
Hedge fund |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 26.60% | 27.80% |
Defined Benefit Plan, Plan Assets, Amount | $ 9,569,000 | $ 9,165,000 |
Hedge fund | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 5,207,000 | 5,299,000 |
Hedge fund | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 0 | 0 |
Hedge fund | Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | $ 4,362,000 | $ 3,866,000 |
Total other securities |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage | 25.00% |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 33.10% | 38.10% |
Defined Benefit Plan, Plan Assets, Amount | $ 11,901,000 | $ 12,533,000 |
Total other securities | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 5,207,000 | 5,299,000 |
Total other securities | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 499,000 | 1,498,000 |
Total other securities | Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 6,195,000 | 5,736,000 |
Nonqualified Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | $ 0 | $ 0 | $ 0

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