Net Loss Per Share (Tables)

12 Months Ended

Dec. 31, 2018

Earnings Per Share [Abstract]

Summary of Outstanding Options, Warrants and preferred stock were Excluded from Computation of Diluted Net Loss Per Share

The following outstanding options, restricted stock units and warrants as of December 31 were excluded from the computation of diluted net loss per share for the periods presented because their effect would have been anti-dilutive (in thousands):

	2018	2017	2016
Options to purchase common stock	5,395	5,335	4,711
Restricted stock units	1,147	313	115
Common stock warrants	535	317	491