Property and Equipment (Details) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2017	Dec. 31, 2016
Property, Plant and Equipment, Gross		$ 2,609	$ 1,430
Less accumulated depreciation and amortization		953	799
Total		1,656	631
Research and Development Equipment [Member]
Property, Plant and Equipment, Gross		$ 1,335	989
Property, Plant and Equipment, Useful Life		5 years
Office and Computer Equipment [Member]
Property, Plant and Equipment, Gross		$ 672	235
Property, Plant and Equipment, Useful Life		3 years
Furniture and Fixtures [Member]
Property, Plant and Equipment, Gross		$ 31	17
Property, Plant and Equipment, Useful Life		7 years
Autos/Trucks [Member]
Property, Plant and Equipment, Gross		$ 306
Property, Plant and Equipment, Useful Life		5 years
Leasehold Improvements [Member]
Property, Plant and Equipment, Gross	[1]	$ 265	$ 189

[1] Shorter of lease term or estimated useful life