Investments (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
Jan. 31, 2021	Mar. 31, 2022	Dec. 31, 2021
Investments [Abstract]
Equity method investments		$ 87.1	$ 93.7
Investments in marketable equity securities		10.1	5.8
Unrealized gain (loss) on marketable equity securities		4.3
Realized gain (loss) on marketable equity securities	$ (5.4)
Investments in non-marketable equity securities		$ 37.7	$ 37.7

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

Amount of investment in equity security without readily determinable fair value.

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Amount of investment in marketable security.

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Amount of realized gain (loss) on investment in marketable security, including other-than-temporary impairment (OTTI).

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Amount of unrealized gain (loss) on investment in marketable security.

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