Restructuring, Business Transformation and Other Cost Saving Initiatives - Narrative (Details) $ in Millions		3 Months Ended		9 Months Ended
	Sep. 26, 2023 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2024 USD ($) Employee	Sep. 30, 2023 USD ($)	Jul. 31, 2023 USD ($)
Human Immunology Biosciences
Restructuring Cost and Reserve [Line Items]
Integration related costs		$ 1.5		$ 1.5
Minimum
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost Remaining						$ 260.0
Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring and Related Cost, Expected Cost Remaining						$ 280.0
2023 Cost Saving Initiatives
Restructuring Cost and Reserve [Line Items]
Expected operating expense reduction	$ 1,000.0
Expected number of positions eliminated | Employee				1,000
Severance Costs		4.6	$ 37.7	$ 20.2	$ 62.6
2023 Cost Saving Initiatives | Restructuring charges
Restructuring Cost and Reserve [Line Items]
Severance Costs		4.6	37.7	20.2	62.6
Reata Integration
Restructuring Cost and Reserve [Line Items]
Severance Costs		0.7	21.0	3.2	21.0
Reata Integration | Minimum
Restructuring Cost and Reserve [Line Items]
Expected cost		35.0		35.0
Reata Integration | Maximum
Restructuring Cost and Reserve [Line Items]
Expected cost		40.0		40.0
Reata Integration | Restructuring charges
Restructuring Cost and Reserve [Line Items]
Severance Costs		$ 0.7	$ 21.0	$ 3.2	$ 21.0