Other Consolidated Financial Statement Detail (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Other Income (Expense), Net
Gain on sale of equity interest in Samsung Bioepis(1)	$ 0.0		$ 0.0	$ (1,505.4)	$ 0.0
Litigation settlement agreement	0.0	$ 900.0	0.0	900.0	0.0
Interest income	(23.9)		(2.6)	(39.4)	(8.2)
Interest expense	59.9		66.3	191.8	187.3
(Gains) losses on investments, net	(101.8)		424.5	167.5	707.2
Foreign exchange (gains) losses, net	11.5		13.7	39.0	23.1
Other, net	(1.7)		1.0	25.2	4.0
Other (income) expense	(56.0)		502.9	(221.3)	913.4
Equity Securities, FV-NI, Gain (Loss), Alternative [Abstract]
Net (gains) losses recognized on equity securities	(109.8)		424.2	158.1	705.9
Less: Net (gains) losses realized on equity securities	(0.5)		(2.7)	0.0	(9.3)
Net unrealized (gains) losses recognized on equity securities	(109.3)		$ 426.9	158.1	$ 715.2
Accrued Expenses and Other
Litigation settlement agreement(1)	900.0			900.0		$ 0.0
Revenue-related reserves for discounts and allowances	983.9			983.9		935.3
Collaboration expense	313.5			313.5		345.1
Royalties and licensing fees	208.6			208.6		234.7
Collaboration expense	260.1			260.1		324.7
Other	769.2			769.2		828.6
Total accrued expense and other	3,305.9			3,305.9		2,535.2
Ionis, Sangamo, Denali and Sage
Equity Securities, FV-NI, Gain (Loss), Alternative [Abstract]
Net unrealized (gains) losses recognized on equity securities	112.5			198.0
Component of accrued expenses and other
Accrued Expenses and Other
Revenue-related reserves for discounts and allowances	$ 854.5			$ 854.5		$ 802.1