Restructuring and Acquisition-Related Costs - Restructuring Reserve Table (Details) - USD ($) $ in Millions	12 Months Ended	39 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019
Restructuring Reserve [Roll Forward]
Restructuring reserve	$ 12.2	$ 4.0	$ 0.3
Restructuring charges	58.4	39.8	44.2
Cash utilization	(59.1)	(31.6)	(10.5)
Non-cash utilization	0.0	0.0	(30.0)
Restructuring reserve	11.5	12.2	4.0	$ 12.2
2016 Restructuring Plan - Employee Severance [Member]
Restructuring Reserve [Roll Forward]
Restructuring charges				2.8
2016 Restructuring Plan - Other Restructuring [Member]
Restructuring Reserve [Roll Forward]
Restructuring charges				29.6
Employee Severance [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve	4.8	2.4	0.3
Restructuring charges	22.3	19.4	2.5
Cash utilization	(25.4)	(17.0)	(0.4)
Non-cash utilization	0.0	0.0	0.0
Restructuring reserve	1.7	4.8	2.4	4.8
Other Restructuring [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve	7.4	1.6	0.0
Restructuring charges	36.1	20.4	11.7
Cash utilization	(33.7)	(14.6)	(10.1)
Non-cash utilization	0.0	0.0	0.0
Restructuring reserve	9.8	7.4	1.6	7.4
Asset Impairment [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve	0.0	0.0	0.0
Restructuring charges	0.0	0.0	30.0
Cash utilization	0.0	0.0	0.0
Non-cash utilization	0.0	0.0	(30.0)
Restructuring reserve	$ 0.0	$ 0.0	$ 0.0	$ 0.0

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

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