Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Intangible assets
Intangible assets, net	$ 995	$ 1,243
Estimated useful life	10 years
Amortization expense	$ 200	200
Weighted Average
Intangible assets
Estimated useful life	4 years
Developed technology
Intangible assets
Total intangible assets	$ 979	979
Accumulated amortization	(582)	(485)
Intangible assets, net	$ 397	494
Estimated useful life	10 years
License agreements
Intangible assets
Total intangible assets	$ 1,508	1,508
Accumulated amortization	(910)	(759)
Intangible assets, net	$ 598	$ 749
Estimated useful life	10 years