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Investments in Marketable Securities - Debt Securities, Available-for-Sale (Details) - USD ($) $ in Millions	Sep. 30, 2022	Dec. 31, 2021
Schedule of Investments [Line Items]
Cost	$ 113.4	$ 14.1
Unrealized losses	(3.1)	(0.1)
Fair value	$ 110.3	$ 14.0

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- Definition

Debt Securities, Available-For-Sale And Trading

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- Definition

Debt Securities, Available-For-Sale And Trading, Accumulated Gross Unrealized Loss, Before Tax

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- Definition

Debt Securities, Available-For-Sale And Trading, Amortized Cost

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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