Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Cash flows from operating activities:
Net income	$ 2,086.2	$ 1,610.3
Adjustments to reconcile net income to net cash flows from operating activities:
Depreciation and amortization	340.4	694.6
Acquired in-process research and development	85.0	120.0
Share-based compensation	81.7	67.3
Deferred income taxes	(57.4)	(20.5)
Other	42.4	73.5
Changes in operating assets and liabilities, net:
Accounts receivable	(187.2)	(301.2)
Inventory	(40.1)	(85.3)
Accrued expenses and other current liabilities	13.3	(452.3)
Income tax assets and liabilities	183.4	(114.7)
Other changes in operating assets and liabilities, net	8.7	(187.3)
Net cash flows provided by operating activities	2,556.4	1,404.4
Cash flows from investing activities:
Proceeds from sales and maturities of marketable securities	6,802.7	3,584.5
Purchases of marketable securities	4,774.3	2,536.0
Contingent consideration paid related to Fumapharm AG acquisition	900.0	600.0
Purchases of property, plant and equipment	(381.5)	(407.7)
Acquired in-process research and development	(85.0)	(120.0)
Acquisitions of intangible assets	(3.0)	(860.3)
Purchase of Ionis Pharmaceuticals, Inc. stock	(463.7)	0.0
Other	2.9	(7.2)
Net cash flows provided by (used in) investing activities	198.1	(946.7)
Cash flows from financing activities:
Purchases of treasury stock	(3,000.0)	(1,365.4)
Payments related to issuance of stock for share-based compensation arrangements, net	(14.3)	(17.8)
Repayment of borrowings	(3.2)	0.0
Net distribution to noncontrolling interest	(38.9)	0.0
Net cash contribution to Bioverativ Inc.	0.0	302.7
Other	(3.7)	33.5
Net cash flows used in financing activities	(3,060.1)	(1,652.4)
Net increase (decrease) in cash and cash equivalents	(305.6)	(1,194.7)
Effect of exchange rate changes on cash and cash equivalents	(18.0)	37.8
Cash and cash equivalents, beginning of the period	1,573.8	2,326.5
Cash and cash equivalents, end of the period	$ 1,250.2	$ 1,169.6