Pension Plans and Other Postretirement Benefit Plans - Net Funded Status of Over-Funded, Underfunded, and Unfunded Pension Plans (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Pension plans and other postretirement benefit plans
Overfunded defined benefit pension plans	$ 23.6	$ 25.0
Underfunded and unfunded defined benefit pension plans	(67.9)	(67.5)
Pension Plans
Pension plans and other postretirement benefit plans
Overfunded defined benefit pension plans	23.6	25.0
Underfunded and unfunded defined benefit pension plans	(67.9)	(67.5)
Pension liabilities included in other current liabilities	(0.9)	(1.2)
Net funded status	(45.2)	(43.7)
Underfunded defined benefit pension plans \| Pension Plans
Pension plans and other postretirement benefit plans
Underfunded and unfunded defined benefit pension plans	(41.5)	(40.8)
Unfunded defined benefit pension plans \| Pension Plans
Pension plans and other postretirement benefit plans
Underfunded and unfunded defined benefit pension plans	$ (26.4)	$ (26.7)

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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- Definition

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

+ References

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- Definition

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

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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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- Definition

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.

+ References

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