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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, 2021 USD ($) plan | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total retirement plan expense | $ 3,685 | $ 2,824 | $ 2,572
401(k) plan |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total retirement plan expense | 3,196 | 2,403 | 2,031
Multiemployer and other defined benefit and pension plans |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total retirement plan expense | $ 78 | 70 | 195
Number of plans | plan | 1 |  |
Other Postretirement Benefits |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Total retirement plan expense | $ 411 | $ 351 | $ 346

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- Details
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- Details
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