Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Intellectual property
Intellectual property	$ 700	$ 700
Less: Accumulated amortization	(662)	(428)
Total, net	38	272
Amortization expense	$ 234	$ 234	$ 194