Condensed Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Income Statement [Abstract]
Product revenues, net	$ 2,690.6	$ 2,374.8
Costs and expenses:
Cost of sales	342.6	266.9
Research and development expenses	789.1	742.6
Acquired in-process research and development expenses	76.8	347.1
Selling, general and administrative expenses	342.7	241.1
Change in fair value of contingent consideration	(0.1)	(1.9)
Total costs and expenses	1,551.1	1,595.8
Income from operations	1,139.5	779.0
Interest income	181.2	122.6
Interest expense	(10.4)	(11.4)
Other (expense) income, net	(31.2)	1.3
Income before provision for income taxes	1,279.1	891.5
Provision for income taxes	179.5	191.7
Net income	$ 1,099.6	$ 699.8
Net income per common share:
Basic (in dollars per share)	$ 4.26	$ 2.72
Diluted (in dollars per share)	$ 4.21	$ 2.69
Shares used in per share calculations:
Basic (in shares)	258.2	257.4
Diluted (in shares)	261.1	260.3