Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Cash flow from operating activities:
Net income	$ 1,632.2	$ 1,161.5	$ 2,961.6
Adjustments to reconcile net income to net cash flow from operating activities:
Depreciation and amortization	673.2	494.8	518.4
Impairment of intangible assets	60.2	0.0	119.6
Excess and obsolescence charges related to inventory	101.9	124.4	336.2
Amortization of acquired inventory step-up	230.0	31.5	0.0
Share-based compensation	291.2	264.2	254.1
Contingent consideration	27.7	0.0	(209.1)
Deferred income taxes	(158.1)	(305.8)	(168.6)
(Gain) loss on strategic investments	101.4	277.1	265.9
(Gain) loss on equity method investment	0.0	0.0	(2.6)
Gain on sale of equity interest in Samsung Bioepis	0.0	0.0	(1,505.4)
Gain on sale of building, net	0.0	0.0	(503.7)
Gain on sale of priority review voucher, net	(88.6)	0.0	0.0
Other	159.6	148.2	208.2
Changes in operating assets and liabilities, net of effects of business acquired:
Accounts receivable	222.3	61.3	(203.4)
Due from anti-CD20 therapeutic programs	(28.1)	(4.6)	(19.0)
Inventory	(273.8)	(130.9)	(320.2)
Accrued expense and other current liabilities	24.6	(201.6)	(113.4)
Income tax assets and liabilities	78.5	(299.0)	(142.3)
Other changes in operating assets and liabilities, net	(178.7)	(73.9)	(92.0)
Net cash flow provided by (used in) operating activities	2,875.5	1,547.2	1,384.3
Cash flow from investing activities:
Purchases of property, plant and equipment	(153.7)	(277.0)	(240.3)
Proceeds from sales and maturities of marketable securities	0.0	7,380.8	3,671.0
Purchases of marketable securities	0.0	(5,140.7)	(3,448.5)
Acquisition, net of cash acquired	(1,074.8)	(6,926.1)
Proceeds from sale of equity interest in Samsung Bioepis	406.8	788.1	990.3
Proceeds from sale of building	0.0	0.0	582.6
Proceeds from sale of priority review voucher, net	88.6	0.0	0.0
Acquisitions of intangible assets	(206.1)	(34.4)	(2.9)
Proceeds from sales of strategic investments	144.7	119.6	0.0
Other	(4.7)	(11.3)	24.4
Net cash flow provided by (used in) investing activities	(799.2)	(4,101.0)	1,576.6
Cash flow from financing activities:
Purchase of treasury stock	0.0	0.0	(750.0)
Payments related to issuance of stock for share-based compensation arrangements, net	(31.3)	(44.3)	(1.9)
Repayments of borrowings and premiums paid	(650.0)	(809.9)	(1,002.2)
Proceeds from borrowings	0.0	997.2	0.0
Net (distribution) contribution to noncontrolling interest	0.0	12.3	12.4
Other	(2.2)	(6.0)	(5.6)
Net cash flow provided by (used in) financing activities	(683.5)	149.3	(1,747.3)
Net increase (decrease) in cash and cash equivalents	1,392.8	(2,404.5)	1,213.6
Effect of exchange rate changes on cash and cash equivalents	(67.7)	35.1	(55.7)
Cash and cash equivalents, beginning of the year	1,049.9	3,419.3	2,261.4
Cash and cash equivalents, end of the year	$ 2,375.0	$ 1,049.9	$ 3,419.3