Net Loss Per Share Attributable to Common Stockholders (Tables)

9 Months Ended

Sep. 30, 2016

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 September 30,				Nine Months Ended September 30,
	2016		2015		2016		2015
Series A convertible preferred stock		—		2,172,520		816,677		2,172,520
Series B convertible preferred stock		—		4,999,976		1,879,553		3,726,832
Unvested restricted common stock		95,415		139,837		105,996		161,979
Options to purchase common stock		1,361,135		644,505		1,017,620		435,022