Fair Value Measurements - Schedule of Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	$ 1,865.3	$ 2,121.6
Available-for-sale debt securities	15,528.4	15,713.4
Equity securities	48.7	34.3
Total	17,442.4	17,869.3
Restricted
Assets, Fair Value Disclosure [Abstract]
Equity securities	47.5	33.3
Corporate bonds
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	10,619.6	10,219.5
U.S. government and government agency obligations
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	3,667.6	4,367.3
Commercial paper
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	689.1	541.1
Certificates of deposit
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	248.0	265.9
Asset-backed securities
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	219.7	242.8
Sovereign bonds
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	84.4	76.8
Level 1
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	613.3	1,127.7
Equity securities	48.7	34.3
Total	662.0	1,162.0
Level 1 \| Corporate bonds
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	0.0	0.0
Level 1 \| U.S. government and government agency obligations
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	0.0	0.0
Level 1 \| Commercial paper
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	0.0	0.0
Level 1 \| Certificates of deposit
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	0.0	0.0
Level 1 \| Asset-backed securities
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	0.0	0.0
Level 1 \| Sovereign bonds
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	0.0	0.0
Level 2
Assets, Fair Value Disclosure [Abstract]
Cash equivalents	1,252.0	993.9
Equity securities	0.0	0.0
Total	16,780.4	16,707.3
Level 2 \| Corporate bonds
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	10,619.6	10,219.5
Level 2 \| U.S. government and government agency obligations
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	3,667.6	4,367.3
Level 2 \| Commercial paper
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	689.1	541.1
Level 2 \| Certificates of deposit
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	248.0	265.9
Level 2 \| Asset-backed securities
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	219.7	242.8
Level 2 \| Sovereign bonds
Assets, Fair Value Disclosure [Abstract]
Available-for-sale debt securities	$ 84.4	$ 76.8

Fair value portion of asset recognized for present right to economic benefit.

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Amount of 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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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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

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