Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Total revenues	$ 4,991.1	$ 4,131.2	$ 3,551.1
Cost of sales:
Cost of sales	394.5	374.3	454.2
Operating expenses:
Research and development	886.0	730.4	878.4
Selling, general and administrative	1,261.1	1,111.8	1,094.4
Acquired in-process research and development	(4.1)	1,183.0	0.0
Amortization of purchased intangible assets	309.6	320.1	320.1
Change in fair value of contingent consideration	11.6	116.5	41.0
Restructuring expenses	12.0	25.5	104.6
Impairment of intangible assets	0.0	0.0	31.0
Total operating expenses	2,476.2	3,487.3	2,469.5
Operating income	2,120.4	269.6	627.4
Other income and expense:
Investment income	100.3	65.3	18.5
Interest expense	(77.8)	(98.2)	(98.4)
Other income and (expense)	35.9	5.5	0.3
Income before income taxes	2,178.8	242.2	547.8
Income tax (benefit) expense	(225.5)	164.6	104.5
Net income	$ 2,404.3	$ 77.6	$ 443.3
Earnings per common share
Basic (in dollars per share)	$ 10.77	$ 0.35	$ 1.98
Diluted (in dollars per share)	$ 10.70	$ 0.35	$ 1.97
Shares used in computing earnings per common share
Basic (in shares)	223.2	222.7	223.9
Diluted (in shares)	224.8	224.5	225.4
Net product sales
Total revenues	$ 4,990.0	$ 4,130.1	$ 3,549.5
Other revenue
Total revenues	$ 1.1	$ 1.1	$ 1.6