Supplemental Financial Information (Other Income) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Supplemental Financial Information [Abstract]
Gain (Loss) on Extinguishment of Debt	$ 0.0	$ 0.0	$ (29.2)	$ 0.0
Gain (Loss) on Sale of Properties	0.0	0.1	27.9	137.7
Net foreign currency exchange gains	3.6	9.8	3.4	25.2
Net periodic pension income	0.1	4.0	0.3	12.1
Other income (expense)	0.2	(0.2)	1.3	(2.3)
Other Nonoperating Income (Expense)	$ 3.9	$ 13.7	$ 3.7	$ 172.7

Amount, before tax, of realized and unrealized gain (loss) from foreign currency transaction.

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

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Other Nonoperating Income (Expense), Other

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Supplemental Financial Information [Abstract]

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