Annual report pursuant to Section 13 and 15(d)

Stock Plans and Stock-Based Compensation - Summary of Stock Option Grants, Including Performance Options (Detail)

v3.21.1
Stock Plans and Stock-Based Compensation - Summary of Stock Option Grants, Including Performance Options (Detail)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2020
USD ($)
$ / shares
shares
Shares Subject to Outstanding Options  
Outstanding at the beginning of period | shares 6,726,695
Options granted | shares 3,611,593
Options exercised | shares (63,633)
Options forfeited | shares (492,931)
Options expired | shares (970,094)
Outstanding as end of period | shares 8,811,630
Vested and expected to vest | shares 8,811,630
Exercisable | shares 4,789,242
Weighted-Average Exercise Price of Options  
Outstanding at the beginning of period | $ / shares $ 7.88
Options granted | $ / shares 4.84
Options exercised | $ / shares 1.44
Options forfeited | $ / shares 11.46
Options expired | $ / shares 9.02
Outstanding as end of period | $ / shares 6.35
Vested and expected to vest | $ / shares 6.35
Exercisable | $ / shares $ 6.57
Weighted-Average Remaining Contractual Term (Years)  
Outstanding 7 years 7 months 6 days
Vested and expected to vest 7 years 7 months 6 days
Exercisable 6 years 5 months 26 days
Aggregate Intrinsic Value (In Thousands)  
Outstanding | $ $ 9,507
Vested and expected to vest | $ 9,507
Exercisable | $ $ 5,734