Intangible Assets - Schedule of Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount		$ 956.3	$ 29.3
Accumulated Amortization		(40.8)	(22.6)
Net Carrying Amount		915.5	6.7
Acquired product rights - Libtayo
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Life (in years)	13 years
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount		946.3	0.0
Accumulated Amortization		(35.7)	0.0
Net Carrying Amount		910.6	0.0
Other intangibles
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Amount		10.0	29.3
Accumulated Amortization		(5.1)	(22.6)
Net Carrying Amount		$ 4.9	$ 6.7
Other intangibles | Minimum
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Life (in years)	5 years
Other intangibles | Maximum
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated Life (in years)	8 years