Equity Transactions (Tables)

12 Months Ended

Dec. 31, 2018

Equity [Abstract]

Summary of Common Stock Reserved for Issuance

A summary of common stock reserved for issuance is as follows as of December 31, 2018 (in thousands):

Equity incentive plans	9,203
Option agreement with Adam R. Craig	1,120
Common stock purchase warrants	514
Series O convertible preferred stock	8,383
Employee stock purchase plan	178
Total common stock reserved	19,398