Pension And Other Benefit Plans - Fair Values Of Pension Plan Assets (Details) - Defined benefit pension plans - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets	$ 75.5	$ 74.4	$ 80.6
Quoted Prices in Active Market (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets	8.5	8.4
Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets	0.0	0.0
Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets	50.2	49.7	$ 50.1
Total
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets	58.7	58.1
Cash and cash equivalents | Quoted Prices in Active Market (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets	8.5	8.4
Cash and cash equivalents | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets	0.0	0.0
Cash and cash equivalents | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets	0.0	0.0
Cash and cash equivalents | Total
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets	8.5	8.4
Insurance contracts | Quoted Prices in Active Market (Level 1)
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets	0.0	0.0
Insurance contracts | Significant Other Observable Inputs (Level 2)
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets	0.0	0.0
Insurance contracts | Significant Unobservable Inputs (Level 3)
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets	50.2	49.7
Insurance contracts | Total
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets	50.2	49.7
Mutual funds | Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, plan assets	$ 16.8	$ 16.3