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Pension Benefits Fair Value of Plan Assets in Heirarchy (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
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 | $ 45,692,000 | $ 36,414,000 | $ 35,941,000
Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 29,590,000 | 26,409,000 |
Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 9,389,000 | 3,208,000 |
Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 6,713,000 | 6,797,000 | 6,195,000
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases | 0 | 400,000 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Realized Gain on Assets | 364,000 | 259,000 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Unrealized Loss on Assets | (448,000) | (57,000) |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Disposition | $ 0 | $ 0 |
Defined Benefit Plan, Equity Securities, US |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 20.30% | 20.70% |
Defined Benefit Plan, Plan Assets, Amount | $ 9,280,000 | $ 7,533,000 |
Defined Benefit Plan, Equity Securities, US | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 6,097,000 | 5,012,000 |
Defined Benefit Plan, Equity Securities, US | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 3,183,000 | 2,521,000 |
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 | 22.70% | 26.40% |
Defined Benefit Plan, Plan Assets, Amount | $ 10,349,000 | $ 9,594,000 |
Defined Benefit Plan, Equity Securities, Non-US | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 10,349,000 | 9,594,000 |
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 | 49.00% |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 43.00% | 47.10% |
Defined Benefit Plan, Plan Assets, Amount | $ 19,629,000 | $ 17,127,000 |
Defined Benefit Plan, Equity Securities | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 16,446,000 | 14,606,000 |
Defined Benefit Plan, Equity Securities | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 3,183,000 | 2,521,000 |
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 | 25.50% | 14.30% |
Defined Benefit Plan, Plan Assets, Amount | $ 11,646,000 | $ 5,220,000 |
Core fixed income | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 11,646,000 | 5,220,000 |
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 | 0.00% | 6.70% |
Defined Benefit Plan, Plan Assets, Amount | $ 0 | $ 2,450,000 |
Corporate Debt Securities | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 0 | 2,450,000 |
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 | 26.00% |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 25.50% | 21.00% |
Defined Benefit Plan, Plan Assets, Amount | $ 11,646,000 | $ 7,670,000 |
Total fixed income securities | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 11,646,000 | 7,670,000 |
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 | 4.60% | 6.80% |
Defined Benefit Plan, Plan Assets, Amount | $ 2,116,000 | $ 2,476,000 |
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 | $ 2,116,000 | $ 2,476,000 |
Defined Benefit Plan, Common Collective Trust |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage | 13.60% | 1.90% |
Defined Benefit Plan, Plan Assets, Amount | $ 6,206,000 | $ 687,000 |
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 | 6,206,000 | 687,000 |
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 | 13.30% | 23.20% |
Defined Benefit Plan, Plan Assets, Amount | $ 6,095,000 | $ 8,454,000 |
Hedge fund | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 1,498,000 | 4,133,000 |
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 | $ 4,597,000 | $ 4,321,000 |
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 | 31.50% | 31.90% |
Defined Benefit Plan, Plan Assets, Amount | $ 14,417,000 | $ 11,617,000 |
Total other securities | Fair Value, Inputs, Level 1 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 1,498,000 | 4,133,000 |
Total other securities | Fair Value, Inputs, Level 2 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 6,206,000 | 687,000 |
Total other securities | Fair Value, Inputs, Level 3 |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | 6,713,000 | 6,797,000 |
Nonqualified Plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan, Plan Assets, Amount | $ 0 | $ 0 | $ 0

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