Marketable Securities - Schedule of Debt Securities Based on Contractual Maturity Dates (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Investments, Debt and Equity Securities [Abstract]
Maturities within one year	$ 5,937.2	$ 6,524.3
Maturities after one year through five years	9,518.9	7,804.8
Maturities after five years	66.0	0.0
Total	$ 15,522.1	$ 14,329.1