Condensed Consolidated Statements of Operations (Unaudited) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Income Statement [Abstract]
Product and service revenue	$ 4,273,385	$ 4,312,885	$ 18,711,555	$ 11,927,135
Research and development contract revenue	502,269	994,244	1,475,338	3,342,187
Licensed technology revenue		163,125		489,375
Total revenue	4,775,654	5,470,254	20,186,893	15,758,697
Cost of product and service revenue	10,848,860	7,565,994	28,552,076	19,187,617
Cost of research and development contract revenue	791,322	1,695,171	2,389,844	5,505,767
Research and development expense	1,284,975	1,478,847	4,089,509	3,647,821
Selling, general and administrative expenses	3,053,434	3,606,505	10,556,495	11,051,020
Gain on sale of leased assets		(673,358)		(673,358)
Amortization of intangible assets	578,090	584,606	1,726,854	1,754,568
Operating loss	(11,781,027)	(8,787,511)	(27,127,885)	(24,714,738)
Interest and other income and net realized losses from available-for-sale securities	80,046	99,740	171,260	220,862
Change in fair value of common stock warrant liability	1,434,866	2,414,267	3,726,667	4,204,787
Interest and other expense and foreign currency gain (loss)	(59,349)	(17,042)	(158,162)	2,675
Net loss	$ (10,325,464)	$ (6,290,546)	$ (23,388,120)	$ (20,286,414)
Loss per share:
Basic and diluted (in dollars per share)	$ (0.27)	$ (0.28)	$ (0.71)	$ (1.16)
Weighted average number of common shares outstanding (in shares)	37,977,052	22,676,114	33,107,175	17,441,767