Employee Benefit Plans - Pension Plans Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2023 USD ($) pensionPlan	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Number of defined benefit plans \| pensionPlan	2
Fair value of plan assets	$ 295.5	$ 270.3
Benefit obligation	374.4	339.9
Items not yet recognized as net periodic pension cost (benefit)	131.8	127.7
Loss on plan obligations		159.3
Net gains due to plan experience	7.3	(19.1)
Accumulated benefit obligations exceed plan assets	361.4	329.5
Accumulated benefit obligations and the fair value of plan assets	295.5	270.3
Net periodic pension cost	19.8	(3.4)	$ (8.9)
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	243.2	221.1
Benefit obligation	267.4	247.1
Unfunded status of plan	$ (24.3)	$ (26.0)

Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Due to Plan Experience

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Number of Defined Benefit Plans

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Amount of gain (loss) from change in actuarial assumptions which (increases) decreases benefit obligation of defined benefit plan. Assumptions include, but are not limited to, interest, mortality, employee turnover, salary, and temporary deviation from substantive plan.

+ References

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of defined benefit plan cost (credit), classified as other.

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Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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Amount of cost (reversal of cost) for pension benefits. Excludes other postretirement benefits.

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