Net Loss per Share (Tables)

12 Months Ended

Dec. 31, 2017

Earnings Per Share [Abstract]

Summary of Computation of Basic and Diluted Net Loss Per Share

The following table summarizes the computation of basic and diluted net loss per share attributable to common stockholders of the Company (in thousands, except per share data):

	December 31,
	2017			2016			2015
Net loss attributable to common stockholders- basic and diluted	$	(84,979	)	$	(95,817	)	$	(82,177	)
Net loss per share- basic and diluted	$	(2.41	)	$	(3.11	)	$	(2.84	)
Weighted-average common shares used to compute net loss per share- basic    and diluted		35,228			30,784			28,964

Summary of Potentially Anti-dilutive Securities Excluded from Computation of Diluted Shares Outstanding

The following potentially dilutive securities outstanding at the end of the years presented have been excluded from the computation of diluted shares outstanding:

	December 31,
	2017		2016		2015
Options to purchase common stock		3,645,456		4,452,700		3,240,969
Restricted stock units		2,518,740		502,027		254,067