Segment Information (Details 1) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Product Information [Line Items]
Total revenue	$ 3,878	$ 5,044
Core [Member]
Product Information [Line Items]
Total revenue	41	26
Optical [Member]
Product Information [Line Items]
Total revenue	3,781	4,615
Wafer [Member]
Product Information [Line Items]
Total revenue		9
Research And Development [Member]
Product Information [Line Items]
Total revenue	$ 56	$ 394