Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment, Changes In Certain Assumptions

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- Definition

Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment, Prior Service Costs

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- Definition

Defined Benefit Plan, Number Of Plans

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- Definition

Defined Benefit Plan, Plan Assets, Concentration of Risk, Percentage

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- Definition

Multiemployer Plans, Cost Recognized

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- Definition

Multiemployer Plans, Settlement And Curtailments

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- Definition

Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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- Definition

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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- Definition

Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year.

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- Definition

Percentage of plan assets to benefit obligation of defined benefit plan.

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- Definition

Amount of increase (decrease) in benefit obligation of defined benefit plan from change in terms of existing plan or initiation of new plan.

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

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- Definition

Amount of cost for defined contribution plan.

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- Definition

Amount, after tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent.

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- Definition

Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

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Retirement Benefits - Narrative (Details) $ in Millions	1 Months Ended	12 Months Ended
Retirement Benefits - Narrative (Details) $ in Millions	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($) plan	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Decrease in pension benefit obligation	$ 21.0
Decreased in prior service costs	75.0
Decrease for plan amendment related to other costs and losses	54.0
Accumulated other comprehensive income net impact	$ 21.0
Contributions expected in 2020		$ 6.5
Accrued retirement benefits		82.5	$ 109.1
Expenses related to employees under Defined Contribution Plans		32.2	20.9	$ 22.1
Multiemployer plans expense			4.0	73.7
Multiemployer plans, curtailment loss and special termination benefits				$ 67.0
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Decrease in pension benefit obligation		(74.7)	0.0
Total accumulated benefit obligation		210.1	199.9
Accrued retirement benefits		$ 77.5	105.2
Pension Plans \| Public equity securities
Defined Benefit Plan Disclosure [Line Items]
Designated percentage invested		32.00%
Pension Plans \| Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Designated percentage invested		5.00%
Pension Plans \| Real estate
Defined Benefit Plan Disclosure [Line Items]
Designated percentage invested		21.00%
Pension Plans \| Other Alternative Investments
Defined Benefit Plan Disclosure [Line Items]
Designated percentage invested		6.00%
Pension Plans \| Fixed Income Securities
Defined Benefit Plan Disclosure [Line Items]
Designated percentage invested		36.00%
Pension Plans \| Switzerland
Defined Benefit Plan Disclosure [Line Items]
Percentage of benefit obligation in Switzerland pension plans		80.00%
Percentage of plan assets in Switzerland pension plans		87.00%
Retiree Health Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Number of plans \| plan		2
Accrued retirement benefits		$ 4.7	$ 3.9