Consolidated Statements of Operations and Comprehensive Income (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Product revenue	$ 71,773,730	$ 68,010,169	$ 61,956,386
Licensing, milestone and contract revenue	3,307,424	3,348,336	2,822,249
Total revenue	75,081,154	71,358,505	64,778,635
Operating expenses
Cost of product revenue	22,765,404	28,988,621	26,783,738
Research & development	7,059,875	5,388,036	6,168,937
Selling, general & administrative	12,936,001	14,728,662	17,858,558
Restructuring charges	(286,843)	2,537,988
Total operating expenses	42,474,437	51,643,307	50,811,233
Income from operations	32,606,717	19,715,198	13,967,402
Interest income (expense), net	(127,186)	(187,777)	(182,388)
Income before income taxes	32,479,531	19,527,421	13,785,014
Provision for income taxes	11,905,010	7,769,961	5,318,334
Net income	20,574,521	11,757,460	8,466,680
Basic net income per share:
Net income (in Dollars per share)	$ 1.46	$ 0.89	$ 0.65
Basic weighted average common shares outstanding (in Shares)	14,086,912	13,260,739	13,064,051
Diluted net income per share:
Net income (in Dollars per share)	$ 1.39	$ 0.82	$ 0.62
Diluted weighted average common shares outstanding (in Shares)	14,825,599	14,344,577	13,747,813
Net income	20,574,521	11,757,460	8,466,680
Other comprehensive income (loss)
Foreign currency translation adjustment	955,535	412,551	(519,405)
Comprehensive income	$ 21,530,056	$ 12,170,011	$ 7,947,275