Intangible Assets - Schedule of Finite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Gross Carrying Amount	$ 4,998	$ 4,982
Accumulated Amortization	(3,517)	(3,433)
Finite-Lived Intangible Assets, Net	1,481	1,549
Patent [Member]
Gross Carrying Amount	673	657
Accumulated Amortization	(314)	(306)
Finite-Lived Intangible Assets, Net	$ 359	351
Patent [Member] \| Minimum [Member]
Finite-Lived Intangible Asset, Useful Life	1 year
Patent [Member] \| Maximum [Member]
Finite-Lived Intangible Asset, Useful Life	17 years
Software [Member]
Finite-Lived Intangible Asset, Useful Life	3 years
Gross Carrying Amount	$ 410	410
Accumulated Amortization	(400)	(398)
Finite-Lived Intangible Assets, Net	$ 10	12
Customer Relationships [Member]
Finite-Lived Intangible Asset, Useful Life	12 years
Gross Carrying Amount	$ 3,370	3,370
Accumulated Amortization	(2,307)	(2,246)
Finite-Lived Intangible Assets, Net	$ 1,063	1,124
Permit [Member]
Finite-Lived Intangible Asset, Useful Life	10 years
Gross Carrying Amount	$ 545	545
Accumulated Amortization	(496)	(483)
Finite-Lived Intangible Assets, Net	$ 49	$ 62