Employee Benefit Plans (Fair Values of Plan Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 1,109.4	$ 1,067.1
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17.4	35.1
Equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	431.9	396.3
Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	457.5	453.1
Assets held by insurance companies and other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	202.6	182.6
Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	776.3	335.6
Level 1 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17.4	34.2
Level 1 | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	401.6	42.9
Level 1 | Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	175.9	181.6
Level 1 | Assets held by insurance companies and other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	181.4	76.9
Level 2
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	329.1	723.7
Level 2 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.9
Level 2 | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	30.3	353.4
Level 2 | Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	281.6	271.5
Level 2 | Assets held by insurance companies and other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17.2	97.9
Level 3
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4.0	7.8
Level 3 | Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Level 3 | Equity securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Level 3 | Fixed income securities
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0.0	0.0
Level 3 | Assets held by insurance companies and other
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 4.0	$ 7.8