Discontinued Operations and Special Charges - Special Charges Liabilities (Details) - Lease Liabilities and Other Exit Costs - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Restructuring Reserve [Roll Forward]
Beginning Balance	$ 2.8	$ 2.8
Charged to expense	0.1	0.7
Paid or otherwise settled	0.0	(0.7)
Ending Balance	$ 2.9	$ 2.8

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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-Name Accounting Standards Codification
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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

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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Amount of decrease in the reserve for full or partial settlement through consideration other than cash.

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