Acquisitions - Human Immunology Biosciences (Details) - USD ($) $ in Millions		12 Months Ended
	Jul. 02, 2024	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Research and development
Business Combination [Line Items]
Share-based compensation expense		$ 115.7	$ 154.1	$ 296.7
Selling, general and administrative
Business Combination [Line Items]
Share-based compensation expense		187.8	198.6	371.7
Human Immunology Biosciences
Business Combination [Line Items]
Total transaction value	$ 1,137.3
Range of outcomes, value, high	650.0
Non-vested equity awards	74.5
Share-based compensation expense	56.4	$ 0.0	$ 56.4	$ 0.0
Working capital adjustment	43.7
Human Immunology Biosciences | Research and development
Business Combination [Line Items]
Share-based compensation expense	42.5
Human Immunology Biosciences | Selling, general and administrative
Business Combination [Line Items]
Share-based compensation expense	13.9
Previously Reported | Human Immunology Biosciences
Business Combination [Line Items]
Total transaction value	$ 1,150.0