Restructuring (Restructuring Liability) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Restructuring Reserve [Roll Forward]
Utilization	$ 13.1	$ 1.2
2020 Repositioning Actions
Restructuring Reserve [Roll Forward]
Utilization	0.5	0.0
2019 Repositioning Actions
Restructuring Reserve [Roll Forward]
Utilization	(0.1)	0.0
2017 Repositioning Actions
Restructuring Reserve [Roll Forward]
Utilization	12.7	$ 1.5
Severance
Restructuring Reserve [Roll Forward]
Beginning balance	24.9
Expense (Gain)	0.1
Adjustments	(0.5)
Utilization	(5.1)
Ending balance	19.4
Severance \| 2020 Repositioning Actions
Restructuring Reserve [Roll Forward]
Beginning balance	4.2
Expense (Gain)	0.0
Adjustments	(0.5)
Utilization	(2.4)
Ending balance	1.3
Severance \| 2019 Repositioning Actions
Restructuring Reserve [Roll Forward]
Beginning balance	16.0
Expense (Gain)	0.1
Adjustments	0.0
Utilization	(2.6)
Ending balance	13.5
Severance \| 2017 Repositioning Actions
Restructuring Reserve [Roll Forward]
Beginning balance	4.7
Expense (Gain)	0.0
Adjustments	0.0
Utilization	(0.1)
Ending balance	$ 4.6

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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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 420
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- Definition

Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Amount of increase (decrease) in the accrual for restructuring costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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