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Other Consolidated Financial Statement (Details Textual) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
	Sep. 26, 2023	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Net gains recognized on the increase in fair value of equity securities		$ 29.8	$ (105.8)	$ 55.5	$ (29.3)
Net gains (losses) realized during the period on equity securities		0.6	(0.7)	5.5	0.9
Other long-term liabilities		556.7		556.7		$ 781.1
Accrued income taxes		191.7		191.7		$ 403.2
Reata Pharmaceuticals, Inc
Total transaction value	$ 6,602.9
Ionis, Sangamo, Denali and Sage
Net gains recognized on the increase in fair value of equity securities		51.4	117.7	68.3	78.0
Sangamo
Net gains recognized on the increase in fair value of equity securities		$ 27.0		$ 17.6
Sage Therapeutics
Net gains recognized on the increase in fair value of equity securities			$ 10.9		$ 47.4