CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities:
Net income	$ 2,364.0	$ 1,323.8
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	174.2	156.0
Non-cash compensation expense	310.5	330.8
Other non-cash items, net	(111.3)	113.2
Deferred taxes	117.9	(110.0)
Changes in assets and liabilities:
Increase in Sanofi, trade, and other accounts receivable	(1,275.3)	(464.5)
Increase in inventories	(402.4)	(227.2)
Decrease in prepaid expenses and other assets	16.4	24.8
Increase in deferred revenue	112.3	166.8
Increase in accounts payable, accrued expenses, and other liabilities	80.8	328.9
Total adjustments	(976.9)	318.8
Net cash provided by operating activities	1,387.1	1,642.6
Cash flows from investing activities:
Purchases of marketable and other securities	(2,642.7)	(2,834.9)
Sales or maturities of marketable and other securities	3,330.3	1,306.4
Capital expenditures	(453.2)	(290.6)
Net cash provided by (used in) investing activities	234.4	(1,819.1)
Cash flows from financing activities:
Proceeds from issuance of long-term debt	1,981.9	0.0
Proceeds from bridge loan facility	1,500.0	0.0
Repayment of bridge loan facility	(1,500.0)	0.0
Proceeds from issuance of Common Stock	2,471.1	163.5
Payments in connection with Common Stock tendered for employee tax obligations	(652.5)	(40.5)
Repurchases of Common Stock	(5,465.7)	(29.4)
Net cash (used in) provided by financing activities	(1,665.2)	93.6
Net decrease in cash, cash equivalents, and restricted cash	(43.7)	(82.9)
Cash, cash equivalents, and restricted cash at beginning of period	1,630.3	1,480.2
Cash, cash equivalents, and restricted cash at end of period	$ 1,586.6	$ 1,397.3