Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Summary of Stock Option Activity (Detail)

v3.19.1
Stockholders' Equity - Summary of Stock Option Activity (Detail)
shares in Thousands
3 Months Ended
Mar. 31, 2019
$ / shares
shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]  
Total Options, Beginning balance | shares 5,385
Total Options, Granted | shares 1,564
Total Options, Exercised | shares 0
Total Options, Forfeited/cancelled/expired | shares (190)
Total Options, Ending balance | shares 6,759
Weighted-Average Exercise Price, Beginning balance | $ / shares $ 5.20
Weighted-Average Exercise Price, Granted | $ / shares 2.00
Weighted-Average Exercise Price, Exercised | $ / shares 0
Weighted-Average Exercise Price, Forfeited/cancelled/expired | $ / shares 6.17
Weighted-Average Exercise Price, Ending balance | $ / shares $ 4.43