Financial Instruments - Summary of Marketable Securities (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Debt Securities, Available-for-Sale, Amortized Cost [Abstract]
Amortized Cost	$ 1,238.9
Gross Unrealized Gains	0.2
Gross Unrealized Losses	0.0
Fair Value	1,239.1
Marketable equity securities:
Amortized Cost	227.7	$ 668.7
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(109.6)	(489.0)
Fair Value	118.1	179.7
Corporate debt securities:
Debt Securities, Available-for-Sale, Amortized Cost [Abstract]
Amortized Cost	246.8
Gross Unrealized Gains	0.0
Gross Unrealized Losses	0.0
Fair Value	246.8
Corporate debt securities, noncurrent
Debt Securities, Available-for-Sale, Amortized Cost [Abstract]
Amortized Cost	290.6
Gross Unrealized Gains	0.2
Gross Unrealized Losses	0.0
Fair Value	290.8
Government securities:
Debt Securities, Available-for-Sale, Amortized Cost [Abstract]
Amortized Cost	560.4
Gross Unrealized Gains	0.0
Gross Unrealized Losses	0.0
Fair Value	560.4
Government securities, noncurrent
Debt Securities, Available-for-Sale, Amortized Cost [Abstract]
Amortized Cost	88.4
Gross Unrealized Gains	0.0
Gross Unrealized Losses	0.0
Fair Value	88.4
Mortgage and other asset backed securities, noncurrent
Debt Securities, Available-for-Sale, Amortized Cost [Abstract]
Amortized Cost	52.7
Gross Unrealized Gains	0.0
Gross Unrealized Losses	0.0
Fair Value	52.7
Marketable equity securities, non-current
Marketable equity securities:
Amortized Cost	227.7	668.7
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(109.6)	(489.0)
Fair Value	$ 118.1	$ 179.7

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

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Amount, before tax, of unrealized gain 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).

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