Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 7,656	$ 6,785
Accumulated Amortization	(4,260)	(3,990)
Net Carrying Value	$ 3,396	$ 2,795
Weighted Average Useful Life	8 years	8 years
Developed technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 3,900	$ 3,900
Accumulated Amortization	(3,900)	(3,900)
Vision development costs [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,885	2,885
Accumulated Amortization	(360)	(90)
Net Carrying Value	$ 2,525	$ 2,795
Weighted Average Useful Life	8 years	8 years
Software development costs [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 871
Accumulated Amortization	0
Net Carrying Value	$ 871