Net Loss Per Share (Tables)

9 Months Ended

Sep. 30, 2018

Earnings Per Share [Abstract]

Weighted-Average Equity Instruments Excluded from Calculation of Diluted Net Loss Per Share

The following weighted-average equity instruments were excluded from the calculation of diluted net loss per share because their effect would have been anti-dilutive for the periods presented:

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2018		2017		2018		2017
Unvested restricted common stock		29,317		52,882		30,587		63,364
Options to purchase common stock		3,075,526		2,294,012		2,930,485		1,846,593