Pension and Savings Plans - Fair Value of Assets in the Master Trust by Asset (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Level 3
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	$ 0.0	$ 0.0	$ 430.4	$ 0.3
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	104.8	116.0	$ 583.3
Pension Plan \| Fair Value, Inputs, Level 1, 2 and 3
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	88.6	95.9
Pension Plan \| Fair Value, Inputs, Level 1, 2 and 3 \| Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	65.3	66.7
Pension Plan \| Fair Value, Inputs, Level 1, 2 and 3 \| U.S. government securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	17.1	23.4
Pension Plan \| Fair Value, Inputs, Level 1, 2 and 3 \| International government securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	1.5	1.5
Pension Plan \| Fair Value, Inputs, Level 1, 2 and 3 \| Asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	0.4	0.5
Pension Plan \| Fair Value, Inputs, Level 1, 2 and 3 \| Cash funds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	4.3	3.8
Pension Plan \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	18.0	23.1
Pension Plan \| Level 1 \| Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	0.0	0.0
Pension Plan \| Level 1 \| U.S. government securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	13.7	19.3
Pension Plan \| Level 1 \| International government securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	0.0	0.0
Pension Plan \| Level 1 \| Asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	0.0	0.0
Pension Plan \| Level 1 \| Cash funds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	4.3	3.8
Pension Plan \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	70.6	72.8
Pension Plan \| Level 2 \| Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	65.3	66.7
Pension Plan \| Level 2 \| U.S. government securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	3.4	4.1
Pension Plan \| Level 2 \| International government securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	1.5	1.5
Pension Plan \| Level 2 \| Asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	0.4	0.5
Pension Plan \| Level 2 \| Cash funds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	0.0	0.0
Pension Plan \| Level 3
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	0.0	0.0
Pension Plan \| Level 3 \| Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	0.0	0.0
Pension Plan \| Level 3 \| U.S. government securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	0.0	0.0
Pension Plan \| Level 3 \| International government securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	0.0	0.0
Pension Plan \| Level 3 \| Asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	0.0	0.0
Pension Plan \| Level 3 \| Cash funds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	0.0	0.0
Pension Plan \| Fair Value Measured at Net Asset Value Per Share \| Private mutual funds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, assets	$ 16.2	$ 20.1