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Employee Benefits - Summary of Total Expense Related to All Postretirement Benefit Plans (Details) - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2024 | Mar. 31, 2023
Defined Benefit Plan Disclosure [Line Items] |  |
Net periodic postretirement benefit cost relating to defined benefit plans | $ 0.3 | $ 2.0
Postretirement Benefit Plans |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined contribution plan, cost | 5.8 | 5.8
Deferred compensation arrangement with individual, compensation expense | 0.7 | 0.2
Multiemployer plan, contributions by employer | 1.5 | 1.4
Net periodic postretirement benefit cost relating to defined benefit plans | 1.5 | 3.1
Total other employee benefit plans | $ 9.5 | $ 10.5

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