Organization, Liquidity and Management's Plan, and Summary of Significant Accounting Policies (Tables)

6 Months Ended

Jun. 30, 2019

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Schedule of Computation of Basic and Diluted Net Loss per Common Share

The following table presents the computation of basic and diluted net loss per common share (in thousands, except share and per share data):

	Three Months Ended June 30,						Six Months Ended June 30,
	2019			2018			2019			2018
Numerator:
Net loss attributable to common stockholders	$	(7,674	)	$	(6,672	)	$	(12,598	)	$	(10,223	)
Denominator:
Weighted-average common shares outstanding		72,104,334			52,973,371			72,021,742			48,955,952
Less: Weighted-average shares subject to repurchase		(183,095	)		(206,260	)		(183,095	)		(225,571	)
Denominator for basic and diluted net loss per share		71,921,239			52,767,111			71,838,647			48,730,381
Net loss per share:
Basic and diluted	$	(0.11	)	$	(0.13	)	$	(0.18	)	$	(0.21	)

Schedule of Potentially Dilutive Securities Not Included in Calculation of Diluted Net Loss per Share

Potentially dilutive securities that are not included in the calculation of diluted net loss per share because their effect is anti-dilutive are as follows (in common equivalent shares):

	As of June 30,
	2019		2018
Common stock warrants		6,013,633		7,855,190
Restricted stock units		427,560		123,625
Common stock subject to repurchase		183,095		183,095
Common stock options		2,599,409		1,924,151
		9,223,697		10,086,061