Basic and Diluted Loss per Common Share (Tables)

12 Months Ended

Dec. 31, 2019

Earnings Per Share [Abstract]

Schedule of Earnings Per Share, Basic and Diluted

The following table sets forth the computation of basic and diluted net loss per share for the years ended December 31 (in thousands, except per share data):

	Year Ended December 31,
	2019		2018		2017
Numerator:
Net loss	$	(50,714)	$	(49,451)	$	(31,007)
Accretion of dividends on convertible preferred stock	—		—		357
Net loss attributable to common stockholders	$	(50,714)	$	(49,451)	$	(31,364)
Denominator
Weighted average common shares outstanding, basic and diluted	65,479,327		62,140,684		49,529,833
Net loss per share attributable to common stockholders, basic and diluted	$	(0.77)	$	(0.80)	$	(0.63)

Summary of Securities Excluded From Calculation of Weighted Average Common Shares

The following securities have been excluded from the calculation of weighted average common shares outstanding because the effect is anti-dilutive or performance or market conditions had not been met at the end of the period:

	Year Ended December 31,
	2019	2018	2017
Stock options	4,458,611	5,021,068	7,010,887
Restricted stock units	1,022,835	1,175,049	731,975