Marketable Securities and Equity Investments - Available-for-Sale Debt Securities at Fair Value (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Total cash equivalents and marketable securities, Fair Value	$ 8,069.1	$ 8,341.3
Cash and cash equivalents
Debt Securities, Available-for-sale [Line Items]
Total cash equivalents and marketable securities, Fair Value	1,012.6	1,687.1
Marketable securities
Debt Securities, Available-for-sale [Line Items]
Total cash equivalents and marketable securities, Fair Value	1,410.6	1,546.3
Long-term marketable securities
Debt Securities, Available-for-sale [Line Items]
Total cash equivalents and marketable securities, Fair Value	$ 5,645.9	$ 5,107.9