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Amount of cash inflow from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as investing activity.

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Financial Instruments and Fair Value Measurements (Summary of Carrying Values and Fair Values of Fixed Rate Debt) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from Sale of Equity Securities	$ 109.4	$ 1.8	$ 109.4	$ 105.4
Equity security with readily determinable fair value		15.4	2.2
Equity security without a readily determinable fair value		56.7	56.7
Net gains (losses) recognized during the period on equity securities		2.9	10.9
Less: Net gains recognized during the period on equity securities		0.0	7.5
Unrealized gains (losses) recognized during the reporting period on equity securities still held at the reporting date		2.9	3.4
Nonrecurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity Securities without readily determinable fair value, cumulative upward adjustment		3.4
Fixed Rate Debt [Member] \| Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed rate long-term debt		3,224.0	2,527.8
Fixed Rate Debt [Member] \| Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed rate long-term debt		$ 2,803.6	$ 2,687.2