Condensed Consolidated Statements of Income - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Income Statement [Abstract]
Product revenues, net	$ 2,483.5	$ 2,334.3	$ 7,351.5	$ 6,628.0
Costs and expenses:
Cost of sales	318.7	289.4	894.2	797.0
Research and development expenses	810.0	645.0	2,338.3	1,846.2
Acquired in-process research and development expenses	51.7	29.0	509.3	92.9
Selling, general and administrative expenses	263.8	246.8	767.5	677.3
Change in fair value of contingent consideration	1.2	(2.6)	(1.3)	(59.3)
Total costs and expenses	1,445.4	1,207.6	4,508.0	3,354.1
Income from operations	1,038.1	1,126.7	2,843.5	3,273.9
Interest income	167.9	46.2	435.2	58.6
Interest expense	(10.9)	(13.7)	(33.5)	(43.2)
Other (expense) income, net	(15.9)	17.2	(13.0)	(133.7)
Income before provision for income taxes	1,179.2	1,176.4	3,232.2	3,155.6
Provision for income taxes	143.9	245.9	581.4	652.5
Net income	$ 1,035.3	$ 930.5	$ 2,650.8	$ 2,503.1
Net income per common share:
Basic (in dollars per share)	$ 4.01	$ 3.63	$ 10.29	$ 9.78
Diluted (in dollars per share)	$ 3.97	$ 3.59	$ 10.18	$ 9.68
Shares used in per share calculations:
Basic (in shares)	258.0	256.5	257.7	255.8
Diluted (in shares)	260.6	259.5	260.4	258.7