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Pension and Other Postretirement Benefits (Schedule of Total Expense for All Retirement Plans) (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2023 USD ($) plan | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total retirement plan expense | $ 4,147 | $ 4,001 | $ 3,685
401(k) plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total retirement plan expense | 3,804 | 3,580 | 3,196
Multiemployer and other defined benefit and pension plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total retirement plan expense | $ 92 | 79 | 78
Number of plans | plan | 1 |  |
Other Postretirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total retirement plan expense | $ 251 | $ 342 | $ 411

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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- Details
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