Net Loss per Share (Tables)

6 Months Ended

Jun. 30, 2017

Earnings Per Share [Abstract]

Summary of Basic and Diluted Net Loss Per Share of Common Stock

The following table summarizes the computation of basic and diluted net loss per share of our common stock for the three and six months ended June 30, 2017 and 2016:

	Three Months Ended June 30,						Six Months Ended June 30,
	2017			2016			2017			2016
	(in thousands, except share and per share data)
Numerator:
Net loss	$	(11,637	)	$	(13,452	)	$	(22,182	)	$	(29,032	)
Denominator:
Weighted-average common shares outstanding, basic and diluted	42,681,287			41,063,613			42,395,450			40,805,641
Net loss per share attributable to common stockholders, basic and diluted	$	(0.27	)	$	(0.33	)	$	(0.52	)	$	(0.71	)

Anti-Dilutive Securities Excluded from Computation Diluted Weighted Average Shares Outstanding

The following potentially dilutive securities outstanding, prior to the use of the treasury stock method or if-converted method, have been excluded from the computation of diluted weighted-average shares outstanding for the respective periods below because they would have been anti-dilutive:

	Three and Six Months Ended June 30,
	2017	2016
Options to purchase common stock	5,041,268	4,766,320
Unvested restricted stock	420,541	811,681
Unvested restricted stock units	1,878,730	619,240
Shares to be issued under ESPP	76,647	103,471
Total	7,417,186	6,300,712