CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Net sales	$ 3,435.3	$ 2,963.7	$ 2,493.7
Cost of sales	875.3	797.4	617.2
Gross profit	2,560.0	2,166.3	1,876.5
Selling, general, and administrative expenses	984.7	904.7	850.7
Research and development expenses	552.6	442.2	382.9
Intellectual property litigation (income) expenses, net (Note 3)	(73.3)	32.6	7.0
Change in fair value of contingent consideration liabilities	(9.9)	1.1	0.2
Special charges, net (Note 4)	59.9	34.5	0.0
Interest expense	23.2	19.2	17.2
Interest income	(20.3)	(10.8)	(7.9)
Other expense, net (Note 15)	8.2	4.9	4.0
Income before provision for income taxes	1,034.9	737.9	622.4
Provision for income taxes (Note 16)	451.3	168.4	127.5
Net income	$ 583.6	$ 569.5	$ 494.9
Earnings per share:
Basic (in dollars per share)	$ 2.77	$ 2.67	$ 2.30
Diluted (in dollars per share)	$ 2.70	$ 2.61	$ 2.25
Weighted-average number of common shares outstanding:
Basic (in shares)	210.9	213.0	215.5
Diluted (in shares)	215.9	217.8	220.3