Quarterly report pursuant to Section 13 or 15(d)

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

v3.20.2
Stockholders' Equity - Summary of Stock Option Activity (Detail) - 2014 EIP and Inducement Plan
$ / shares in Units, $ in Thousands
9 Months Ended
Sep. 30, 2020
USD ($)
$ / shares
shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Outstanding, Shares, beginning balance | shares 6,934,262
Granted, Shares | shares 2,504,925
Exercised, Shares | shares (132,911)
Forfeited or expired, Shares | shares (1,081,714)
Outstanding, Shares, ending balance | shares 8,224,562
Outstanding, Weighted Average Exercise Price, beginning balance | $ / shares $ 28.25
Granted, Weighted Average Exercise Price | $ / shares 11.75
Exercised, Weighted Average Exercise Price | $ / shares 13.47
Forfeited or expired, Weighted Average Exercise price | $ / shares 30.89
Outstanding, Weighted Average Exercise Price, ending balance | $ / shares $ 23.12
Outstanding, Weighted Average Remaining Contractual Term 6 years 6 months
Aggregate intrinsic value | $ $ 3,985