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Employee Benefits - Summary of Total Expense (Benefit) Related to All Postretirement Benefit Plans (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2023 | Mar. 31, 2022
Defined Benefit Plan Disclosure [Line Items] |  |
Net periodic postretirement benefit cost relating to defined benefit plans | $ 2.0 | $ 1.4
Postretirement Benefit Plans |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Defined contribution plan, cost | 5.8 | 5.7
Deferred compensation arrangement with individual, compensation expense | 0.2 | (0.3)
Multiemployer plan, contributions by employer | 1.4 | 1.2
Net periodic postretirement benefit cost relating to defined benefit plans | 3.1 | 3.2
Total other employee benefit plans | $ 10.5 | $ 9.8

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