Net Loss Per Share - Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Numerator:
Net loss	$ (10,376)	$ (9,134)
Net loss attributable to common stockholders for basic and diluted loss per share	$ (10,376)	$ (9,134)
Denominator:
Net loss per share attributable to common stockholders - basic	$ (0.09)	$ (0.12)
Net loss per share attributable to common stockholders - Diluted	$ (0.09)	$ (0.12)
Weighted average number of common shares outstanding - basic	113,248,937	76,378,569
Weighted average number of common shares outstanding - Diluted	113,248,937	76,378,569
Exercise of the pre-funded warrants	24,930,483	16,718,418