Consolidated statements of operations (unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Income Statement [Abstract]
Revenue	$ 8,036	$ 11,115	$ 36,773	$ 29,977
Cost of goods sold	17,496	17,433	61,001	46,087
Gross loss	(9,460)	(6,318)	(24,228)	(16,110)
Operating expenses:
General and administrative	2,949	2,137	7,534	6,542
Sales and marketing	337	370	1,136	1,133
Research and development	446	641	1,413	1,518
Loss on disposal of assets	680	129	665	556
Loss from operations	(13,872)	(9,595)	(34,976)	(25,859)
Other income:
Interest income	22	13	66	39
Interest expense	(24)	(24)	(71)	(71)
Realized (loss) gain on foreign currency translation	(137)	(208)	98	(514)
Total other (expense) income	(139)	(219)	93	(546)
Loss before income taxes	(14,011)	(9,814)	(34,883)	(26,405)
Income tax benefit	298	3,974	292	11,295
Net loss	$ (13,713)	$ (5,840)	$ (34,591)	$ (15,110)
Net loss per common share
Basic	$ (0.53)	$ (0.26)	$ (1.35)	$ (0.67)
Diluted	$ (0.53)	$ (0.26)	$ (1.35)	$ (0.67)
Weighted average common shares outstanding used in computing net loss per common share	26,110,651	22,578,608	25,711,532	22,563,196