Supplemental Financial Information Supplemental Financial Information (Other Income) (Details) - USD ($) $ in Millions	1 Months Ended	4 Months Ended	8 Months Ended	12 Months Ended
Mar. 31, 2020	Apr. 30, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Supplemental Financial Information [Abstract]
Net Periodic Defined Benefits Expense (Reversal of Expense), Excluding Service Cost Component		$ 5.4	$ 8.7	$ 14.6	$ 5.8
Net foreign currency exchange gains (losses)		13.4	8.1	(11.0)	(7.4)
Business Combination, Bargain Purchase, Gain Recognized And Adjustment		0.0	0.0	(6.3)	637.0
Gain (Loss) on Extinguishment of Debt	$ 3.1	0.0	0.0	3.1	194.1
Proceeds from Legal Settlements		0.0	0.0	0.0	200.0
Payments for Legal Settlements		0.0	0.0	0.0	(20.3)
Other Nonoperating Expense		1.1	0.1	3.8	4.8
Other, net		25.9	38.1	16.0	1,006.2
Gain (Loss) on Sale of Properties		$ 6.0	$ 21.2	$ 11.8	$ 1.8

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of expense (reversal of expense) for net periodic benefit cost components, excluding service cost component, of defined benefit plan. Amount includes, but is not limited to, interest cost, expected (return) loss on plan asset, amortization of prior service cost (credit), amortization of (gain) loss, amortization of transition (asset) obligation, settlement (gain) loss, curtailment (gain) loss and certain termination benefits.

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Amount of expense related to nonoperating activities, classified as other.

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Amount of income (expense) related to nonoperating activities, classified as other.

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The amount of cash paid for the settlement of litigation or for other legal issues during the period.

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Cash received for the settlement of litigation during the current period.

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Business Combination, Bargain Purchase, Gain Recognized And Adjustment

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Supplemental Financial Information [Abstract]

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