Summary of Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2017

The table below presents shares underlying stock options, restricted stock units, and employee stock purchase plan rights that were excluded from the calculation of the weighted average number of shares outstanding used for the calculation of diluted net loss per share. These are excluded from the calculation due to their anti-dilutive effect for the three and nine months ended September 30, 2017 and 2016 (shares in thousands):

	Three Months Ended				Nine Months Ended
	September 30,				September 30,
	2017		2016		2017		2016
Weighted average number of anti-dilutive potential shares:
Stock options		17,629		15,851		17,424		15,506
Restricted stock units		1,313		699		1,211		519
Employee stock purchase plan rights		—		5		11		2
Total		18,942		16,555		18,646		16,027