Consolidated statements of operations (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Statement [Abstract]
Revenue	$ 11,115	$ 19,942	$ 29,977	$ 47,152
Cost of goods sold	17,433	17,497	46,087	48,104
Gross (loss) profit	(6,318)	2,445	(16,110)	(952)
Operating expenses:
General and administrative	2,137	2,530	6,542	6,880
Sales and marketing	370	417	1,133	1,346
Research and development	641	639	1,518	1,712
Loss (gain) on disposal of assets	129		556	(5)
Loss from operations	(9,595)	(1,141)	(25,859)	(10,885)
Other income:
Interest income	13	12	39	68
Interest expense	(24)		(71)
Realized (loss) gain on foreign currency translation	(208)	277	(514)	308
Realized gain on investments		8		8
Total other (expense) income	(219)	297	(546)	384
Loss before income taxes	(9,814)	(844)	(26,405)	(10,501)
Income tax benefit	3,974	1,116	11,295	6,094
Net income (loss)	$ (5,840)	$ 272	$ (15,110)	$ (4,407)
Net income (loss) per common share
Basic	$ (0.26)	$ 0.01	$ (0.67)	$ (0.20)
Diluted	$ (0.26)	$ 0.01	$ (0.67)	$ (0.20)
Weighted average common shares outstanding used in computing net income (loss) per common share
Basic	22,578,608	22,524,611	22,563,196	22,519,171
Diluted	22,578,608	23,050,618	22,563,196	22,519,171