v3.25.2
Fair Value Measurements - Schedule of Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($)
$ in Millions
Jun. 30, 2025
Dec. 31, 2024
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities $ 14,046.6 $ 14,329.1
Corporate bonds    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 8,959.5 8,220.6
U.S. government and government agency obligations    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 3,663.9 4,817.0
Commercial paper    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 573.2 548.7
Certificates of deposit    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 417.4 381.1
Asset-backed securities    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 372.2 279.3
Sovereign bonds    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 60.4 82.4
Measured on a recurring basis    
Assets, Fair Value Disclosure [Abstract]    
Cash equivalents 850.1 1,452.2
Equity securities 1,485.4 1,095.3
Total assets 16,382.1 16,876.6
Liabilities, Fair Value Disclosure [Abstract]    
Contingent consideration 10.3 52.3
Measured on a recurring basis | Restricted    
Assets, Fair Value Disclosure [Abstract]    
Equity securities 34.7 43.2
Measured on a recurring basis | Corporate bonds    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 8,959.5 8,220.6
Measured on a recurring basis | U.S. government and government agency obligations    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 3,663.9 4,817.0
Measured on a recurring basis | Commercial paper    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 573.2 548.7
Measured on a recurring basis | Certificates of deposit    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 417.4 381.1
Measured on a recurring basis | Asset-backed securities    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 372.2 279.3
Measured on a recurring basis | Sovereign bonds    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 60.4 82.4
Measured on a recurring basis | Level 1    
Assets, Fair Value Disclosure [Abstract]    
Cash equivalents 224.1 1,264.2
Equity securities 1,485.4 1,095.3
Total assets 1,709.5 2,359.5
Liabilities, Fair Value Disclosure [Abstract]    
Contingent consideration 0.0 0.0
Measured on a recurring basis | Level 1 | Corporate bonds    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 0.0 0.0
Measured on a recurring basis | Level 1 | U.S. government and government agency obligations    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 0.0 0.0
Measured on a recurring basis | Level 1 | Commercial paper    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 0.0 0.0
Measured on a recurring basis | Level 1 | Certificates of deposit    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 0.0 0.0
Measured on a recurring basis | Level 1 | Asset-backed securities    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 0.0 0.0
Measured on a recurring basis | Level 1 | Sovereign bonds    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 0.0 0.0
Measured on a recurring basis | Level 2    
Assets, Fair Value Disclosure [Abstract]    
Cash equivalents 626.0 188.0
Equity securities 0.0 0.0
Total assets 14,672.6 14,517.1
Liabilities, Fair Value Disclosure [Abstract]    
Contingent consideration 0.0 0.0
Measured on a recurring basis | Level 2 | Corporate bonds    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 8,959.5 8,220.6
Measured on a recurring basis | Level 2 | U.S. government and government agency obligations    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 3,663.9 4,817.0
Measured on a recurring basis | Level 2 | Commercial paper    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 573.2 548.7
Measured on a recurring basis | Level 2 | Certificates of deposit    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 417.4 381.1
Measured on a recurring basis | Level 2 | Asset-backed securities    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 372.2 279.3
Measured on a recurring basis | Level 2 | Sovereign bonds    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 60.4 82.4
Measured on a recurring basis | Level 3    
Assets, Fair Value Disclosure [Abstract]    
Cash equivalents 0.0 0.0
Equity securities 0.0 0.0
Total assets 0.0 0.0
Liabilities, Fair Value Disclosure [Abstract]    
Contingent consideration 10.3 52.3
Measured on a recurring basis | Level 3 | Corporate bonds    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 0.0 0.0
Measured on a recurring basis | Level 3 | U.S. government and government agency obligations    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 0.0 0.0
Measured on a recurring basis | Level 3 | Commercial paper    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 0.0 0.0
Measured on a recurring basis | Level 3 | Certificates of deposit    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 0.0 0.0
Measured on a recurring basis | Level 3 | Asset-backed securities    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 0.0 0.0
Measured on a recurring basis | Level 3 | Sovereign bonds    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities $ 0.0 $ 0.0