Net Loss per Share (Tables)

12 Months Ended

Dec. 31, 2016

Net Loss per Share

Basic and diluted net loss per share attributable to common stockholders

	Year Ended
	December 31,
	2016		2015		2014
Numerator:
Net loss	$	(48,079)	$	(20,563)	$	(8,517)
Accretion of redeemable convertible preferred stock		—		(2,566)		(2,054)
Net loss attributable to common stockholders	$	(48,079)	$	(23,129)	$	(10,571)
Denominator:
Weighted average shares of common stock outstanding		21,415,733		6,637,678		2,730,427
Less: Weighted average shares of unvested restricted common stock outstanding		—		(530,636)		(1,010,345)
Weighted average common shares outstanding used in calculating net loss per share attributable to common stockholders, basic and diluted		21,415,733		6,107,042		1,720,082
Net loss per share attributable to common stockholders, basic and diluted	$	(2.25)	$	(3.79)	$	(6.15)

Potential common shares excluded from the calculation of diluted net loss per share attributable to common stockholders

	2016	2015	2014
Stock options to purchase common stock	2,702,350	1,738,524	500,262
Restricted stock unit awards	219,614	53,800	—
Unvested restricted common stock	—	—	759,538
Convertible preferred stock (as converted to common stock)	—	—	7,924,919
	2,921,964	1,792,324	9,184,719