Consolidated Condensed Statements of Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Product revenues	$ 232,625	$ 223,818	$ 681,059	$ 644,168
Cost of sales	155,931	148,892	464,628	436,967
Gross margin	76,694	74,926	216,431	207,201
Operating expenses:
Net research and development expenses	19,745	14,934	54,552	44,459
Acquisition transaction expenses	22		693
Selling, general and administrative expenses	29,512	22,543	81,533	71,546
Total operating expenses	49,279	37,477	136,778	116,005
Operating income	27,415	37,449	79,653	91,196
Interest expense	(660)	(759)	(2,287)	(1,867)
Revaluation of derivatives		(134)		(1,151)
Foreign currency (loss) gain	(873)	420	88	748
Other income	359	487	754	944
Earnings before income tax	26,241	37,463	78,208	89,870
Income tax expense	6,018	9,798	27,646	22,891
Net income	$ 20,223	$ 27,665	$ 50,562	$ 66,979
Basic earnings per share	$ 0.55	$ 0.77	$ 1.39	$ 1.86
Diluted earnings per share	$ 0.55	$ 0.76	$ 1.38	$ 1.84
Weighted average number of shares – basic	36,477,044	36,110,360	36,425,626	35,951,430
Weighted average number of shares – diluted	36,594,581	36,481,711	36,558,363	36,390,042