Other Consolidated Financial Statement Detail (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Other Income (Expense), Net
Gain on sale of equity interest in Samsung Bioepis(1)	$ (1,505.4)	$ 0.0	$ (1,505.4)	$ 0.0
Litigation agreement in principle	900.0	0.0	900.0	0.0
Interest income	(12.6)	(2.7)	(15.5)	(5.6)
Interest expense	65.8	56.4	131.9	121.1
Gains (losses) on investments, net	78.2	(153.9)	269.3	282.7
Foreign exchange gains (losses), net	19.2	0.8	27.5	9.4
Other, net	26.2	3.0	26.9	2.9
Other (income) expense	(428.6)	(96.4)	(165.3)	410.5
Equity Securities, FV-NI, Gain (Loss), Alternative [Abstract]
Net gains (losses) recognized on equity securities	(77.2)	154.3	(267.9)	(281.8)
Less: Net gains (losses) realized on equity securities	(0.7)	0.4	(0.5)	6.6
Net unrealized gains (losses) recognized on equity securities	(76.5)	$ 153.9	(267.4)	$ (288.4)
Accrued Expenses and Other
Litigation agreement in principle(1)	900.0		900.0		$ 0.0
Revenue-related reserves for discounts and allowances	983.8		983.8		935.3
Collaboration expense	281.5		281.5		345.1
Royalties and licensing fees	216.2		216.2		234.7
Collaboration expense	261.8		261.8		324.7
Other	793.0		793.0		828.6
Total accrued expense and other	3,298.5		3,298.5		2,535.2
Ionis, Sangamo, Denali and Sage
Equity Securities, FV-NI, Gain (Loss), Alternative [Abstract]
Net unrealized gains (losses) recognized on equity securities	75.3
Component of accrued expenses and other
Accrued Expenses and Other
Revenue-related reserves for discounts and allowances	$ 846.0		$ 846.0		$ 802.1