CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
Revenue	$ 439,618	$ 406,814
Cost of goods sold	221,704	215,493
Gross profit	217,914	191,321
Operating expenses:
Research and development	44,561	41,983
Selling, general and administrative	107,683	90,252
Loss on sale of business	10,178	0
Total operating expenses	162,422	132,235
Earnings from operations	55,492	59,086
Interest expense	4,052	4,453
Interest income	(956)	(271)
Other income, net	(2,219)	(660)
Earnings before income taxes	54,615	55,564
Income tax provision	15,420	12,993
Net earnings	$ 39,195	$ 42,571
Net earnings per share:
Basic earnings per share (in dollars per share)	$ 0.28	$ 0.31
Diluted earnings per share (in dollars per share)	$ 0.28	$ 0.31
Weighted Average Number of Shares Outstanding, Basic	138,504	136,359
Weighted Average Number of Shares Outstanding, Diluted	140,994	138,239