Quarterly report pursuant to Section 13 or 15(d)

Stock Option and Incentive Plans - Summary of Stock Option Activity (Detail)

v3.7.0.1
Stock Option and Incentive Plans - Summary of Stock Option Activity (Detail)
 3 Months Ended
Mar. 31, 2017
USD ($)
$ / shares
shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]  
Number of Options, Options outstanding, Beginning balance | shares 4,691,746
Number of Options, Granted | shares 1,250,000
Number of Options, Expired | shares (33,964)
Number of Options, Options outstanding, Ending balance | shares 5,907,782
Number of Options, Vested and exercisable, Ending Balance | shares 3,813,157
Weighted Average Exercise Price, Options outstanding, Beginning balance | $ / shares $ 4.62
Weighted Average Exercise Price, Granted | $ / shares 1.75
Weighted Average Exercise Price, Expired | $ / shares 4.11
Weighted Average Exercise Price, Options outstanding, Ending balance | $ / shares 4.00
Weighted Average Exercise Price, Vested and exercisable, Ending balance | $ / shares $ 4.69
Weighted Average Remaining Contractual Life (in years), Options outstanding 6 years 3 months 7 days
Weighted Average Remaining Contractual Life (in years), Vested and exercisable 4 years 9 months 29 days
Aggregate Intrinsic value, Options outstanding | $ $ 0
Aggregate Intrinsic value, Vested and exercisable | $ $ 0