Intangible Assets - Summary of Intangible Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	$ 14,388	$ 14,985
Accumulated Amortization	(8,485)	(7,781)
Net Carrying Amount	5,903	7,204
Total	16,437	17,389
Net	7,952	9,608
Trade names and trademarks
Finite-Lived Intangible Assets [Line Items]
Gross carrying value, indefinite lived	1,008	1,008
Patents in process
Finite-Lived Intangible Assets [Line Items]
Gross carrying value, indefinite lived	1,041	1,396
Licenses
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	1,414	1,414
Accumulated Amortization	(1,166)	(1,066)
Net Carrying Amount	248	348
Patents and know how
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	9,093	9,180
Accumulated Amortization	(4,908)	(4,475)
Net Carrying Amount	4,185	4,705
Customer and supplier relationships
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	3,761	4,271
Accumulated Amortization	(2,351)	(2,202)
Net Carrying Amount	1,410	2,069
Non-compete agreements
Finite-Lived Intangible Assets [Line Items]
Gross carrying value	120	120
Accumulated Amortization	(60)	(38)
Net Carrying Amount	$ 60	$ 82