Goodwill and Other Intangible Assets - Schedule of Intangible Assets and Goodwill (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Indefinite-Lived Intangible Assets [Line Items]
Intangible assets, gross (excluding goodwill)	$ 849.3	$ 841.6
Accumulated Amortization	(23.4)	(1.7)
Intangible assets, net (excluding goodwill), total	825.9	839.9
Marketed Products
Indefinite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	238.0	238.0
Accumulated Amortization	(21.9)	(1.7)
Finite-lived intangible assets, net, total	$ 216.1	236.3
Assembled Workforce
Indefinite-Lived Intangible Assets [Line Items]
Estimated Useful lives	3 years
Finite-lived intangible assets, gross	$ 7.7	0.0
Accumulated Amortization	(1.5)	0.0
Finite-lived intangible assets, net, total	$ 6.2	0.0
Minimum | Marketed Products
Indefinite-Lived Intangible Assets [Line Items]
Estimated Useful lives	10 years
Maximum | Marketed Products
Indefinite-Lived Intangible Assets [Line Items]
Estimated Useful lives	12 years
In-process research and development
Indefinite-Lived Intangible Assets [Line Items]
Indefinite-lived intangible assets (excluding goodwill)	$ 603.6	$ 603.6