v3.26.1
Fair Value Measurements - Schedule of Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Assets, Fair Value Disclosure [Abstract]    
Cash equivalents $ 1,336.0 $ 2,121.6
Available-for-sale debt securities 15,189.2 15,713.4
Equity securities 177.9 34.3
Total 16,703.1 17,869.3
Restricted    
Assets, Fair Value Disclosure [Abstract]    
Equity securities 114.0  
Corporate bonds    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 10,751.9 10,219.5
U.S. government and government agency obligations    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 3,303.5 4,367.3
Commercial paper    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 558.3 541.1
Certificates of deposit    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 304.1 265.9
Asset-backed securities    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 193.1 242.8
Sovereign bonds    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 78.3 76.8
Level 1    
Assets, Fair Value Disclosure [Abstract]    
Cash equivalents 1,205.3 1,127.7
Equity securities 177.9 34.3
Total 1,383.2 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 130.7 993.9
Equity securities 0.0 0.0
Total 15,319.9 16,707.3
Level 2 | Corporate bonds    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 10,751.9 10,219.5
Level 2 | U.S. government and government agency obligations    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 3,303.5 4,367.3
Level 2 | Commercial paper    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 558.3 541.1
Level 2 | Certificates of deposit    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 304.1 265.9
Level 2 | Asset-backed securities    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities 193.1 242.8
Level 2 | Sovereign bonds    
Assets, Fair Value Disclosure [Abstract]    
Available-for-sale debt securities $ 78.3 $ 76.8