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Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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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	9 Months Ended
	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from the sale of equity securities	$ 109.4	$ 0.0	$ 109.4
Equity investments with readily determinable fair values		2.1		$ 2.2
Equity investment without readily determinable fair value		56.7		56.7
Net gains (losses) recognized during the period on equity securities		(0.1)	10.9
Less: Net gains recognized during the period on equity securities sold during the period		0.0	7.5
Unrealized gains (losses) recognized during the reporting period on equity securities still held at the reporting date		(0.1)	$ 3.4
Fixed Rate Debt \| Carrying value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed rate debt		3,544.6		2,858.4
Fixed Rate Debt \| Fair value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed rate debt		3,095.6		$ 3,017.8
Nonrecurring Basis
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment in equity securities without readily determinable fair values, cumulative upward adjustment		$ 3.4