Financial Instruments - Summary of Marketable Securities (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
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
Debt Securities, Trading, and Equity Securities, FV-NI, Cost [Abstract]
Amortized Cost	$ 227.7	227.7
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(43.7)	(109.6)
Fair Value	184.0	118.1
Corporate Debt Securities Current
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 Current
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
Equity Securities, Non-Current
Debt Securities, Trading, and Equity Securities, FV-NI, Cost [Abstract]
Amortized Cost	227.7	227.7
Gross Unrealized Gains	0.0	0.0
Gross Unrealized Losses	(43.7)	(109.6)
Fair Value	$ 184.0	$ 118.1

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