UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net Loss	$ (8,400)	$ (6,892)	$ (16,152)	$ (14,876)
Unrealized Loss on Available-for-Sale Debt Instrument Investments	(1)	(6)	(8)	(13)
Foreign Currency Translation Adjustments	0	1	3	7
Comprehensive Loss	$ (8,401)	$ (6,897)	$ (16,157)	$ (14,882)