Summary of Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2020

Summary of Significant Accounting Policies [Abstract]

Inventory, Major Classes, Policy [Policy Text Block]

	As of March 31,		As of December 31,
	2020		2019
	(in thousands)
Raw materials	$	2,218	$	3,182
Work-in-process	$	1,117	$	153
Finished goods	812		908
Total inventory	$	4,147	$	4,243