Financial Instruments (Details 1) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Marketable equity securities
Amortized Cost	$ 928.4	$ 979.9
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(598.9)	(563.1)
Fair Value	329.5	416.8
Equity Securities, Current
Marketable equity securities
Amortized Cost	11.7	31.6
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(11.0)	(21.0)
Fair Value	0.7	10.6
Equity Securities, Non-Current
Marketable equity securities
Amortized Cost	916.7	948.3
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(587.9)	(542.1)
Fair Value	$ 328.8	$ 406.2

Equity Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax

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Equity Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, Before Tax

+ References

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- Definition

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483467/210-10-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482736/825-10-45-1A

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Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479440/944-210-S99-1

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