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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 investment in equity security without readily determinable fair value.

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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
	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Proceeds from Sale of Equity Securities		$ 109.4	$ 109.4	$ 105.4	$ 0.0
Equity security with readily determinable fair value			2.2	101.9
Equity security without a readily determinable fair value			56.7	50.0
Net gains recognized during the period on equity securities			10.9	131.5
Less: Net gains recognized during the period on equity securities			7.5	63.4
Unrealized gains recognized during the reporting period on equity securities still held at the reporting date			3.4	68.1
Nonrecurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Equity investments without readily determinable fair value, upward price adjustment	$ 3.4			0.0
Fixed Rate Debt [Member] \| Carrying Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed rate debt			2,858.4	2,101.8
Fixed Rate Debt [Member] \| Fair Value [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Fixed rate debt			$ 3,017.8	$ 2,341.1