Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Restricted Stock Activity (Detail)

v3.8.0.1
Stockholders' Equity - Restricted Stock Activity (Detail) - Restricted Stock [Member]
9 Months Ended
Sep. 30, 2017
$ / shares
shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]  
Number of shares, Unvested balance | shares 10,094,095
Number of shares, Restricted stock granted | shares 1,325,396
Number of shares, Restricted stock vested | shares (213,333)
Number of shares, Restricted stock units granted | shares 930,000
Number of shares, Restricted stock units forfeited | shares (15,000)
Number of shares, Restricted stock units vested | shares (214,625)
Number of shares, Unvested balance | shares 11,906,533
Weighted average grant price, Unvested balance | $ / shares $ 2.49
Weighted average grant price, Restricted stock granted | $ / shares 2.70
Weighted average grant price, Restricted stock vested | $ / shares 2.75
Weighted average grant price, Restricted stock units granted | $ / shares 4.31
Weighted average grant price, Restricted stock units forfeited | $ / shares 2.98
Weighted average grant price, Restricted stock units vested | $ / shares 3.44
Weighted average grant price, Unvested balance | $ / shares $ 2.63