Consolidated Condensed Statements of Income - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
Product revenues	$ 215,714	$ 206,909
Cost of sales	147,472	140,339
Gross margin	68,242	66,570
Operating expenses:
Net research and development expenses	15,696	14,548
Acquisition transaction expenses	37
Selling, general and administrative	22,624	24,945
Total operating expenses	38,357	39,493
Operating income	29,885	27,077
Interest expense	(677)	(564)
Revaluation of derivatives loss		(964)
Foreign currency gain (loss)	(1,835)	435
Other income	365	195
Earnings before income tax	27,738	26,179
Income tax expense	15,845	6,359
Net income	$ 11,893	$ 19,820
Basic earnings per share	$ 0.33	$ 0.55
Diluted earnings per share	$ 0.33	$ 0.55
Weighted average number of shares – basic	36,356,973	35,769,190
Weighted average number of shares – diluted	36,550,863	36,244,695