Net Loss Per Common Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Basic and diluted net loss per common share calculation:
Net loss	$ (9,842)	$ (5,725)
Net loss and comprehensive loss	$ (9,842)	$ (5,725)
Weighted average common shares outstanding (in shares)	160,508,373	96,332,324
Net loss per share of common stock, basic and diluted (in dollars per share)	$ (0.06)	$ (0.06)
Outstanding securities excluded from computation of diluted weighted shares outstanding (in shares)	14,342,476	11,290,706
Employee Stock Option
Basic and diluted net loss per common share calculation:
Outstanding securities excluded from computation of diluted weighted shares outstanding (in shares)	10,350,543	7,590,430
Restricted Stock Units
Basic and diluted net loss per common share calculation:
Outstanding securities excluded from computation of diluted weighted shares outstanding (in shares)	3,696,342	3,077,185
Warrants
Basic and diluted net loss per common share calculation:
Outstanding securities excluded from computation of diluted weighted shares outstanding (in shares)	295,591	623,091