Net Loss per Common Share - Schedule of Reconciliation of Numerators and Denominators Used In Computing Net Loss From Continuing Operations Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Numerator:
Net loss	$ (18,767)	$ (16,133)
Denominator:
Weighted-average number of shares used in computing net loss per share, basic and diluted	42,190,457	3,437,345
Net loss per share, basic and diluted	$ (0.44)	$ (4.69)