Pension Plans and Other Retirement Plans (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Funded status of fully funded, underfunded, and unfunded pension plans:
Overfunded defined benefit pension plans	$ 5.7	$ 0.0
Unfunded defined benefit pension plans	(433.1)	(502.4)
Pension liabilities included in other current liabilities	(14.7)	(15.0)
Net funded status	$ (442.1)	(517.4)
Defined contribution retirement plan
Percentage that the employer contributes of employee contributions under 401(k) plan	100.00%
Maximum percentage of employee compensation match by employer to defined contribution plan	6.00%
Costs related to defined contribution retirement plan	$ 12.6	11.5	$ 11.1
Pension Plans
Pension plans and other postretirement benefit plans
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	160.9	0.0
Funded status of fully funded, underfunded, and unfunded pension plans:
Overfunded defined benefit pension plans	5.7	0.0
Net funded status	(442.1)	(517.4)
Defined Benefit Plan, Benefit Obligation	1,332.7	1,648.7	1,543.3
Underfunded Plan [Member]
Funded status of fully funded, underfunded, and unfunded pension plans:
Unfunded defined benefit pension plans	(67.1)	(110.5)
Unfunded Plan [Member]
Funded status of fully funded, underfunded, and unfunded pension plans:
Unfunded defined benefit pension plans	(366.0)	(391.9)
Domestic Plan [Member] \| Pension Plans
Pension plans and other postretirement benefit plans
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	160.9	0.0
Funded status of fully funded, underfunded, and unfunded pension plans:
Overfunded defined benefit pension plans	5.7	0.0
Net funded status	(156.0)	(215.8)
Defined Benefit Plan, Benefit Obligation	$ 1,027.1	$ 1,325.6	1,274.2
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	4.22%	3.57%
Domestic Plan [Member] \| Underfunded Plan [Member] \| Pension Plans
Funded status of fully funded, underfunded, and unfunded pension plans:
Net funded status	$ (64.6)	$ (107.3)
Defined Benefit Plan, Benefit Obligation	897.6	1,217.1
Domestic Plan [Member] \| Unfunded Plan [Member] \| Pension Plans
Funded status of fully funded, underfunded, and unfunded pension plans:
Net funded status	(97.1)	(108.5)
Defined Benefit Plan, Benefit Obligation	97.1	108.5
Domestic Plan [Member] \| Overfunded Plan [Member] \| Pension Plans
Funded status of fully funded, underfunded, and unfunded pension plans:
Net funded status	5.7
Defined Benefit Plan, Benefit Obligation	32.4
Foreign Plan [Member] \| Pension Plans
Pension plans and other postretirement benefit plans
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	0.0	0.0
Funded status of fully funded, underfunded, and unfunded pension plans:
Overfunded defined benefit pension plans	0.0	0.0
Net funded status	(286.1)	(301.6)
Defined Benefit Plan, Benefit Obligation	$ 305.6	$ 323.1	$ 269.1
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	2.17%	1.84%
Foreign Plan [Member] \| Underfunded Plan [Member] \| Pension Plans
Funded status of fully funded, underfunded, and unfunded pension plans:
Net funded status	$ (3.2)	$ (3.2)
Defined Benefit Plan, Benefit Obligation	22.7	24.7
Foreign Plan [Member] \| Unfunded Plan [Member] \| Pension Plans
Funded status of fully funded, underfunded, and unfunded pension plans:
Net funded status	(282.9)	(298.4)
Defined Benefit Plan, Benefit Obligation	282.9	$ 298.4
Lump Sum Distribution [Member]
Pension plans and other postretirement benefit plans
Defined Benefit Plan, Benefit Obligation, Benefits Paid	42.2
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	43.5
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement, Gain	1.3
Annuity Settlement [Member]
Pension plans and other postretirement benefit plans
Defined Benefit Plan, Benefit Obligation, Benefits Paid	116.4
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement	117.4
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement, Gain	$ 1.0

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- Definition

Amount of liability, recognized in statement of financial position, for defined benefit pension plan, classified as current. Excludes other postretirement benefit plan.

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

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

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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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Amount of payment, which decreases benefit obligation of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract. Excludes decreases to benefit obligation for remeasurement due to settlement.

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Amount of (increase) decrease to benefit obligation of defined benefit plan from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Includes, but is not limited to, lump-sum cash payment to participant in exchange for right to receive specified benefits, purchase of nonparticipating annuity contract and change from remeasurement.

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Amount of cost for defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan.

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