Intangible Assets, net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Intangible asset amortization (2019, less than)	$ 100	$ 100
Finite-lived intangible assets, amortization expense, next 12 months (less than $1 million)	100
Finite-lived intangible assets, amortization expense, year two (less than $1 million)	100
Finite-lived intangible assets, amortization expense, year three (less than $1 million)	100
Finite-lived intangible assets, amortization expense, year four (less than $1 million)	100
Finite-lived intangible assets, amortization expense, year five (less than $1 million)	$ 100
Remaining amortization period	14 years 10 months 25 days
Patents
Finite-Lived Intangible Assets [Line Items]
Finite-lived intangible assets, gross	$ 465	721
Accumulated amortization - Patents	(199)	(221)
Intangibles, net	$ 266	$ 500