Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity (Deficit) - Schedule of Restricted Stock Activity (Detail)

v3.8.0.1
Stockholders' Equity (Deficit) - Schedule of 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]  
Shares, Forfeited (22,018)
2014 Plan Stock Options/Stock Issuance Plan and 2017 Stock Incentive Plan [Member]  
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Shares, Unvested, Beginning Balance 208,886
Shares, Granted 52,433
Shares, Forfeited (22,018)
Shares, Vested (78,399)
Shares, Unvested, Ending Balance 160,902
Weighted Average Grant Date Fair Value, Unvested, Beginning Balance | $ / shares $ 4.80
Weighted Average Grant Date Fair Value, Granted | $ / shares 14.79
Weighted Average Grant Date Fair Value, Forfeited | $ / shares 8.43
Weighted Average Grant Date Fair Value, Vested | $ / shares 7.82
Weighted Average Grant Date Fair Value, Unvested, Ending Balance | $ / shares $ 6.08