CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash flows from operating activities:
Net income	$ 3,953.6	$ 4,338.4	$ 8,075.3
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	421.0	341.4	286.2
Stock-based compensation expense	885.0	725.0	601.7
Losses (gains) on marketable and other securities, net	266.4	36.8	(387.0)
Other non-cash items, net	(0.1)	368.0	568.7
Deferred income taxes	(837.8)	(746.4)	(147.1)
Acquired in-process research and development in connection with asset acquisition	0.0	195.0	0.0
Changes in assets and liabilities:
(Increase) decrease in accounts receivable	(338.8)	707.8	(1,927.4)
Increase in inventories	(271.7)	(696.5)	(494.3)
Increase in prepaid expenses and other assets	(120.1)	(148.6)	(240.7)
Increase (decrease) in deferred revenue	37.9	32.4	(120.2)
Increase (decrease) in accounts payable, accrued expenses, and other liabilities	598.6	(138.4)	866.1
Total adjustments	640.4	676.5	(994.0)
Net cash provided by operating activities	4,594.0	5,014.9	7,081.3
Cash flows from investing activities:
Purchases of marketable and other securities	(11,646.0)	(7,487.9)	(7,048.1)
Sales or maturities of marketable and other securities	9,442.2	5,550.5	2,215.3
Capital expenditures	(718.6)	(590.1)	(551.9)
Payments for Libtayo intangible asset	(207.8)	(1,026.8)	0.0
Acquisitions, net of cash acquired	(54.9)	(230.3)	0.0
Net cash used in investing activities	(3,185.1)	(3,784.6)	(5,384.7)
Cash flows from financing activities:
Proceeds from issuance of Common Stock	1,145.5	1,519.5	1,672.3
Payments in connection with Common Stock tendered for employee tax obligations	(700.6)	(445.7)	(1,032.7)
Repurchases of Common Stock	(2,235.0)	(2,082.8)	(1,645.4)
Net cash used in financing activities	(1,790.1)	(1,009.0)	(1,005.8)
Effect of exchange rate changes on cash, cash equivalents, and restricted cash	(0.4)	0.0	0.0
Net (decrease) increase in cash, cash equivalents, and restricted cash	(381.6)	221.3	690.8
Cash, cash equivalents, and restricted cash at beginning of period	3,119.4	2,898.1	2,207.3
Cash, cash equivalents, and restricted cash at end of period	2,737.8	3,119.4	2,898.1
Supplemental disclosure of cash flow information
Cash paid for interest (net of amounts capitalized)	73.1	53.7	55.8
Cash paid for income taxes	$ 870.3	$ 1,502.4	$ 1,218.4