Intangible Assets (Schedule of Finite-Lived Intangible Assets) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Intangible assets
Intangible assets, net	$ 932		$ 995
Estimated useful life	10 years
Amortization expense	$ 100	$ 100
Weighted Average
Intangible assets
Estimated useful life	3 years 9 months
Developed technology
Intangible assets
Total intangible assets	$ 979		979
Accumulated amortization	(607)		(582)
Intangible assets, net	$ 372		397
Estimated useful life	10 years
License agreements
Intangible assets
Total intangible assets	$ 1,508		1,508
Accumulated amortization	(948)		(910)
Intangible assets, net	$ 560		$ 598
Estimated useful life	10 years