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Investments in Marketable Securities - Debt Securities, Available-for-Sale (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Available-for-Sale |  |
Cost | $ 252.3 | $ 0.0
Unrealized losses | (1.3) | 0.0
Fair value | 251.0 | 0.0
Trading |  |
Cost | 19.7 | 14.1
Unrealized losses | (1.7) | (0.1)
Fair value | $ 18.0 | $ 14.0

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- Definition Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 + Details
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